Remove pinning to 8.14.0.

[cmacknz]

What the title says. 8.15.0-SNAPSHOT exists, remove version pinning to 8.14.0-SNAPSHOT.

[elasticmachine]

Pinging @elastic/elastic-agent (Team:Elastic-Agent)

[mergify]

This pull request does not have a backport label. Could you fix it @cmacknz? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v./d./d./d is the label to automatically backport to the 8./d branch. /d is the digit

NOTE: backport-skip has been added to this pull request.

[mergify]

This pull request is now in conflicts. Could you fix it? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b remove-8.14-version-pin upstream/remove-8.14-version-pin
git merge upstream/main
git push upstream remove-8.14-version-pin

[cmacknz]

The automation should do this tomorrow, #4768

At which point this just becomes removing the skipped test.

[cmacknz]

Automation update is in #4773

[elastic-sonarqube]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

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