doc: update commit-queue documentation

update the commit-queue contributing documentation by:
 - removing the references of the feature being experimental
 - clarifying that it applies to mergeable pull requests

PR-URL: #58275
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Ulises Gascón <ulisesgascongonzalez@gmail.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>

Author: dario-piotrowicz

doc/contributing/commit-queue.md

@@ -1,10 +1,8 @@
 # Commit queue
 
-> Stability: 1 - Experimental
-
 _tl;dr: You can land pull requests by adding the `commit-queue` label to it._
 
-Commit Queue is an experimental feature for the project which simplifies the
+Commit Queue is a feature for the project which simplifies the
 landing process by automating it via GitHub Actions. With it, collaborators can
 land pull requests by adding the `commit-queue` label to a PR. All
 checks will run via `@node-core/utils`, and if the pull request is ready to
@@ -18,7 +16,7 @@ implementation details, reasoning for design choices, and current limitations.
 From a high-level, the Commit Queue works as follow:
 
 1. Collaborators will add `commit-queue` label to pull requests ready to land
-2. Every five minutes the queue will do the following for each pull request
+2. Every five minutes the queue will do the following for each mergeable pull request
    with the label:
    1. Check if the PR also has a `request-ci` label (if it has, skip this PR
       since it's pending a CI run)