fix: correct workflow reference in good-first-issue-comment docs (#62)

The docs said the script was triggered via `manage-issue-header` but
after the event-based workflow restructuring it is triggered via
`issue-label`.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: rtibblesbot

docs/community-automations.md

@@ -38,7 +38,7 @@ In `scripts/constants.js` set:
 
 # `good-first-issue-comment`
 
-Posts a guidance comment when the `good first issue` label is applied to an issue (triggered via the `manage-issue-header` workflow). Explains the `/assign` command, issue limits, cooldown, and links to contributing guidelines.
+Posts a guidance comment when the `good first issue` label is applied to an issue (triggered via the `issue-label` workflow). Explains the `/assign` command, issue limits, cooldown, and links to contributing guidelines.
 
 - Only posts if the issue also has `help wanted` label
 - Deletes any previous guidance comment from the bot before posting a new one