Update the --openjdk_testrepo arg name in runAqaArgParse.py

Describe the bug
In the runAqaArgParse.py file, the --openjdk_testrepo arg name should be updated to --aqa-testrepo

Expected behavior
The run-aqa should later take in --aqa-testrepo arg

Open runAqaArgParse.py and trace how the run-aqa entry point defines and consumes the existing argument. Verify the updated --aqa-testrepo name is accepted by run-aqa and that the old argument name is no longer required.

Written by the indexing model from the issue text.