Fix failing installation of the xmllint tooling.

…actions

A number of predefined actions have had major release, which warrant an update the workflow(s).

These updates don't actually contain any changed functionality, they are mostly just a change of the Node version used by the action itself (from Node 14 to Node 16).

Refs:
* https://github.com/actions/checkout/releases

…fix-parentheses

WP/CronInterval: bug fix for parentheses

This allows for a time calculation to be wrapped in parentheses.

Fixes 2025

---

Note: just looking at the code, I can see multiple additional improvements which could/should be made:
* Only search for close parenthesis as a "valueEnd" if the `$valueStart` token is an open parenthesis.
* Allow for more assignment operators - the new schedule could be build up bit by bit and only assigned to the array later.

These additional things are not addressed here. This just addresses the immediate issue.

README.md: Update the minimum supported PHP version

The action used to install Composer packages and handle the caching has released a new major (and some follow-up patch releases), which means, the action reference needs to be updated to benefit from it.

Includes adding `--no-interaction` to "plain" Composer commands to potentially prevent CI hanging if, for whatever reason, interaction would be needed in the future.

Refs:
* https://github.com/ramsey/composer-install/releases/tag/2.0.0
* https://github.com/ramsey/composer-install/releases/tag/2.0.1
* https://github.com/ramsey/composer-install/releases/tag/2.0.2

This commit makes the necessary adjustments to the test matrix to account for that.

Note: the protected branch settings should be adjusted after this change to include the two new PHP 8.1 builds.

... as `E_ALL` does not always contain _all_ errors across PHP versions.

Previously, in Travis, when the same branch was pushed again and the "Auto cancellation" option on the "Settings" page had been turned on (as it was for most repos), any still running builds for the same branch would be stopped in favour of starting the build for the newly pushed version of the branch.

To enable this behaviour in GH Actions, a `concurrency` configuration needs to be added to each workflow for which this should applied to.

More than anything, this is a way to be kind to GitHub by not wasting resources which they so kindly provide to us for free.

Refs:
* https://github.blog/changelog/2021-04-19-github-actions-limit-workflow-run-or-job-concurrency/
* https://docs.github.com/en/actions/learn-github-actions/workflow-syntax-for-github-actions#concurrency

The `dealerdirect/phpcodesniffer-composer-installer` Composer plugin is used to register external PHPCS standards with PHPCS.

As of Composer 2.2.0, Composer plugins need to be explicitly allowed to run. This adds the necessary configuration for that.

Refs:
* https://blog.packagist.com/composer-2-2/#more-secure-plugin-execution

…-function-to-list

PHP/NoSilencedErrors: add two functions to the ignore list

... as WP now includes WebP support.

... to the default "ignore" list.

The `libxml_disable_entity_loader()` function is deprecated in PHP 8.0, but a call to the function is still needed in select circumstances, in which case silencing the deprecation warning is perfectly acceptable.

…or-reporting

GH Actions: turn display_errors on

Turns out the default setting for `error_reporting` used by the SetupPHP action is `error_reporting=E_ALL & ~E_DEPRECATED & ~E_STRICT` and `display_errors` is set to `Off`.

For the purposes of CI, I'd recommend running with `E_ALL` and `display_errors=On` to ensure **all** PHP notices are shown.

In this script, error_reporting was already enabled, but the error display was not yet fixed. Sorted now.

Bug report template: various improvements

After the umpteenth time of getting a non-reproducible bug report (not just in this repo, mind you), I figured it may help to add some more guidance to the bug report template.

More important changes:
* Ask for the actual CLI command people have used.
* Ask for the custom ruleset used (if used).
* Give some guidance on how to find out the version numbers of the tooling used.

... which show through in PRs, even when the code in those files has not been adjusted in the PR.

There's only one such warning remaining now, which is _actual_ commented out code.

…lass-to-core

OneObjectStructurePerFile: move from `Extra` to `Core`

…lations-in-pr

Per the discussion had on Slack about this initiated by GaryJones.
WP Core currently has 27 violations against this rule.

In `Extra` the error message was changed and downgraded to a `warning`.

Now the sniff will be added to `Core`, per this PR, the:
* Message text will still be changed a little to be clearer, but will be stricter.
* The message will be an `error` and not be downgraded to a `warning`.

To do:
- [ ] Add a rule to this effect to the handbook.

... as the `quicktest` workflow is run on `push` events, not on PRs, so displaying results in a PR is not relevant (and is done via the `test` workflow which _is_ run on `pull` events anyhow).

The cs2pr tool will allow to display the results from an action run in checkstyle format in-line in the PR code view, which should improve usability of the workflow results.

Ref: https://github.com/staabm/annotate-pull-request-from-checkstyle

…n-php-8.1

GH Actions: get the tests running on PHP 8.1 (nightly)

Letting PHPUnit read the config file causes an error on PHP 8.1 in combination with PHPUnit 7.

For now, special case the test run on PHP 8.1 and pass the only necessary config from the configuration file on via CLI arguments.

…rim-2

PHP 8.1 compatibility: fix deprecation notice [2]

PHP 8.1 compatibility: fix deprecation notice [1]