Expand readme guide

.github/workflows/slack-notifier.yml

@@ -47,12 +47,14 @@ jobs:
         id: rate-limit
         run: |
           # Check if the last message was sent within the timeout
-          echo "Preparing to send message:\n"
-          echo "\"$MESSAGE\"\n"
+          echo "Preparing to send message:"
+          echo
+          echo "\"$MESSAGE\""
+          echo
 
           if [ -f last-sent-${{ inputs.message-label }}.txt ]
           then
-            LAST_SENT=$( cat last-sent.txt )
+            LAST_SENT=$( cat last-sent-${{ inputs.message-label }}.txt )
             echo "Last sent: $LAST_SENT"
             NOW=$( date +%s )
             echo "Now: $NOW"

README.md

@@ -232,3 +232,5 @@ jobs:
 channel. See the
 [slackapi/slack-github-action](https://github.com/slackapi/slack-github-action?tab=readme-ov-file#technique-2-slack-app)
 documentation for more information.
+If you are using a slack app, make sure to add it to the channel.
+See formatting options in the [Slack API documentation](https://api.slack.com/reference/surfaces/formatting).