Add support for workflow triggers without a push or PR event

[drpump]

User Story Description

As a Software Developer,

I want to run the linter action without a push or pull request,

so I can define my own triggers/events for running the linter action.

Acceptance Criteria

• Linter runs correctly with a workflow_dispatch trigger on the current branch
• Linter runs correctly with a workflow_dispatch trigger against selected branch or commit sha (i.e. dispatch input)
• Linter runs correctly with a workflow_call trigger against a specified branch or commit sha parameter

Sprint Ready Checklist

• Acceptance criteria defined
• Team understands acceptance criteria
• Team has defined solution / steps to satisfy acceptance criteria
• Acceptance criteria is verifiable / testable
• External / 3rd Party dependencies identified