[JENKINS-73943] Remove legacy checkUrl usage in AggregatedTestResutPublisher/config.jelly

[yaroslavafenkin]

https://issues.jenkins.io/browse/JENKINS-73943

I've renamed the check method and dropped checkUrl attribute completely to let https://github.com/jenkinsci/jenkins/blob/dc4ad7e1a872e6dd9504f6c1ff1f95d84ca6046b/core/src/main/java/hudson/util/FormValidation.java#L625-L727 do its magic and wire things up for us.
While doCheck sounded generic to me I found no places in code referencing it, so I assume it's safe to rename.

Testing done

https://www.loom.com/share/27c91cc2a4d9480c867ed7cca651bd77?sid=ad8da66b-e52e-4e6e-bfc1-3b9525fb384d

https://www.loom.com/share/aaca1ff0b6274d44a102257baacc9fd9?sid=c8d997ed-11d7-4165-825c-ce5d2defcee7

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue

[yaroslavafenkin]

Infrastructure issue in the Jenkins security scan run:

Run wget --no-verbose https://downloads.apache.org/maven/maven-3/$MAVEN_VERSION/binaries/apache-maven-$MAVEN_VERSION-bin.tar.gz
failed: Connection timed out.
failed: Connection timed out.
failed: Network is unreachable.
failed: Network is unreachable.

[basil]

Thanks for the PR!