.github: Bump slackapi/slack-github-action from 1.24.0 to 1.26.0

Bumps [slackapi/slack-github-action](https://github.com/slackapi/slack-github-action) from 1.24.0 to 1.26.0.
- [Release notes](https://github.com/slackapi/slack-github-action/releases)
- [Commits](slackapi/slack-github-action@v1.24.0...v1.26.0)

---
updated-dependencies:
- dependency-name: slackapi/slack-github-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/govulncheck.yml

@@ -24,7 +24,7 @@ jobs:
 
       - name: Post to slack
         if: failure() && github.event_name == 'schedule'
-        uses: slackapi/slack-github-action@v1.24.0
+        uses: slackapi/slack-github-action@v1.26.0
         env:
           SLACK_BOT_TOKEN: ${{ secrets.GOVULNCHECK_BOT_TOKEN }}
         with: