Assess adding `SUBMISSION_COMMENT` task action for submission comments

[manjitapandey]

Is your feature request related to a problem? Please describe.

• We have an endpoint to submit comments.
• We can't distinguish between task comments or submission comments.

Describe the solution you'd like

• Possibly refactor COMMENT action --> TASK_COMMENT
• Add SUBMISSION_COMMENT action to enum.
• Allow the endpoint to receive either a task or submission comment.
• These will be filtered / displayed differently on the frontend.

Additional context related to #1617 The UI for posting and viewing comments is below: