Build/Test Tools: Revert Slack messaging changes.

This reverts [56404], [56405], [56406].

More testing is needed to ensure multiple messages are not sent unintentionally.

Unprops desrosj.
See #58867.

git-svn-id: https://develop.svn.wordpress.org/trunk@56407 602fd350-edb4-49c9-b593-d223f7449a82

.github/workflows/slack-notifications.yml

@@ -71,11 +71,6 @@ jobs:
               run_id: ${{ github.run_id }},
             });
 
-            // All workflows will restart once when a failure is encountered. Don't notify Slack on the first failure.
-            if ( '${{ inputs.calling_status }}' == 'failure' && workflow_run.data.run_attempt == 1 ) {
-              return 'first-failure';
-            }
-
             // When a workflow has been restarted to fix a failure, check the previous run attempt.
             if ( workflow_run.data.run_attempt > 1 ) {
               const previous_run = await github.rest.actions.getWorkflowRunAttempt({
@@ -162,7 +157,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
     needs: [ prepare ]
-    if: ${{ ( contains( fromJson( '["failure", "startup_failure"]' ), needs.prepare.outputs.previous_conclusion ) || failure() ) && needs.prepare.outputs.previous_conclusion != 'first-failure' }}
+    if: ${{ inputs.calling_status == 'failure' || failure() }}
 
     steps:
       - name: Post failure notifications to Slack