ci: Turn off title validation for single commit PRs (Unity-Technologies#3313)

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When the semantic commit action was added into the branch, the default
squash commit for a pr with only a single commit was the commit name and
not the PR title. Since then, Github has [added a feature to allow
configuration of the
default](https://github.com/orgs/community/discussions/16271) and we
have that setting set in our repo.

This PR turns off the validation of commits as the check is not valid
anymore.

Author: EmandM

.github/workflows/conventional-pr.yml

@@ -1,6 +1,6 @@
 name: Conventional PR
 
-# Controls when the action will run. 
+# Controls when the action will run.
 on:
   pull_request:
     branches:
@@ -17,7 +17,7 @@ jobs:
     steps:
       - name: semantic-pull-request
         # Internal Unity mirror available at jesseo/action-semantic-pull-request, but actions from private repos aren't supported, so continue to use the public one below
-        uses: amannn/action-semantic-pull-request@b7a9a97cb10fa6e1ae02647e718798175f6b1f1d
+        uses: amannn/action-semantic-pull-request@v5
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
@@ -34,4 +34,4 @@ jobs:
           # For work-in-progress PRs you can typically use draft pull requests from Github. However, private repositories on the free plan don't have this option and therefore this action allows you to opt-in to using the special '[WIP]' prefix to indicate this state. This will avoid the validation of the PR title and the pull request checks remain pending. Note that a second check will be reported if this is enabled.
           #wip: # optional
           # When using "Squash and merge" on a PR with only one commit, GitHub will suggest using that commit message instead of the PR title for the merge commit, and it's easy to commit this by mistake. Enable this option to also validate the commit message for one commit PRs.
-          validateSingleCommit: true # optional
+          # validateSingleCommit: true # optional