Fix the broken sonar workflow and apply reusable sonar workflow

[agileshaw]

The sonar workflow was broken because the triggering workflow name contains a comma, which the square-bracket list notation ("[ ]") treated as a separator between two names (PR workflow running lint checkers and unit and functional tests instead of PR workflow running lint checkers, unit and functional tests). This PR fixes this issue.

Additionally, with the base sonar integration being added to bootstack-actions, we should apply the reusable workflow.

Notes:

• This PR relies on the changes introduced in https://github.com/canonical/bootstack-actions/pull/22. Therefore, we should not merge the former before the latter.
• The changes in sonar.yaml file will not take effect until they land in the default branch