Bump rtCamp/action-slack-notify from 2.3.0 to 2.3.1 (#335)

Bumps [rtCamp/action-slack-notify](https://github.com/rtcamp/action-slack-notify) from 2.3.0 to 2.3.1.
- [Release notes](https://github.com/rtcamp/action-slack-notify/releases)
- [Commits](rtCamp/action-slack-notify@v2.3.0...v2.3.1)

---
updated-dependencies:
- dependency-name: rtCamp/action-slack-notify
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/releasability.yaml

@@ -123,7 +123,7 @@ jobs:
       - name: Post status to Slack
         # Note: using env.SLACK_WEBHOOK here because secrets are not allowed in the if block.
         if: env.SLACK_WEBHOOK != '' && inputs.post-to-slack
-        uses: rtCamp/[email protected].0
+        uses: rtCamp/[email protected].1
         env:
           SLACK_CHANNEL: knative-release
           SLACK_USERNAME: knative/release

.github/workflows/release-note.yaml

@@ -136,7 +136,7 @@ jobs:
     - name: Post status to Slack
       # Note: using env.SLACK_WEBHOOK here because secrets are not allowed in the if block.
       if: ${{ always() && env.SLACK_WEBHOOK != '' }}
-      uses: rtCamp/[email protected].0
+      uses: rtCamp/[email protected].1
       env:
         SLACK_CHANNEL: knative-release
         SLACK_USERNAME: knative/release