fix(projectHistoryLogs): rename incorrectly-formatted action TASK-944

[rgraber]

🗒️ Checklist

1. run linter locally
2. update all related docs (API, README, inline, etc.), if any
3. draft PR with a title <type>(<scope>)<!>: <title> TASK-1234
4. tag PR: at least frontend or backend unless it's global
5. fill in the template below and delete template comments
6. review thyself: read the diff and repro the preview as written
7. open PR & confirm that CI passes
8. request reviewers, if needed
9. delete this section before merging

📣 Summary

Change the action modify_sharing to modify-sharing in project history logs for consistency.

👷 Description for instance maintainers

Change the AuditAction modify_sharing to modify-sharing, including a migration to update existing logs. Also adds the migration for all the new audit action types, although this migration seems to be a no-op in SQL.

👀 Preview steps

1. ℹ️ have an account and a project
2. Go to Project > Settings > Connect Projects and enable data sharing. Select a specific question to share.
3. 🔴 [on main] Go to api/v2/assets/<uid>/history. Notice the action for the latest project history log is modify_sharing
4. 🟢 [on PR] After running migrations, reload the history endpoint. Notice the action is now modify-sharing
5. [on PR] Select another question to share
6. 🟢 [on PR] Reload the endpoint. The latest log should have action=modify-sharing

💭 Notes

I didn't even realize this needed a migration until I ran ./manage makemigrations audit_log. It seems to work fine without the migration but this way there will be no unexpected changes next time we have to make a real migration.
The migration of existing logs should be pretty light since it's a fairly rare type of log.