ci: Fix tokens action

[witwash]

Summary

• updated trigger to act only on the last file. I'm planning to rewrite the action from the design-tokens, so it would not push after every commit. Then this trigger won't be needed.
• updated gh pr command

Testing steps

Check if the action will trigger and run successfully.

Follow-up issues

Is there some action/cleanup needed after this PR is merged or deployed (e.g. consolidate some part outside the scope of this PR, etc)? Create issues for it with deadline and note them here and in the PR comments.

Check during review

• Verify against Jira issue.
• Is the PR over 300 additions? Consider rejecting it with advice to split it. Is it over 500 additions? It should definitely be rejected.
• Unused code removed.
• Build passing.
• Is it a bug fix? Check that it is covered by a proper test (unit or integration).