wprkflows/bot: increase frequency to every 5 minutes

This makes reactions to merge comments and all the labeling a bit
quicker. Lower the number of backlog items to process per run
accordingly, so that we don't really need more API requests for it.

.github/workflows/bot.yml

@@ -7,7 +7,9 @@ name: Bot
 
 on:
   schedule:
-    - cron: '05,15,25,35,45,55 * * * *'
+    # Run every 5m
+    # i.e., at each of the listed minutes, every hour
+    - cron: '02,07,12,17,22,27,32,37,42,47,52,57 * * * *'
   workflow_call:
     inputs:
       headBranch:

ci/github-script/bot.js

@@ -587,7 +587,7 @@ module.exports = async ({ github, context, core, dry }) => {
         state: 'open',
         sort: 'created',
         direction: 'asc',
-        per_page: 100,
+        per_page: 50,
         after: cursor,
       })