Bump spring-io/spring-doc-actions from 0.0.19 to 0.0.20

Bumps [spring-io/spring-doc-actions](https://github.com/spring-io/spring-doc-actions) from 0.0.19 to 0.0.20.
- [Commits](spring-io/spring-doc-actions@c203826...e282691)

---
updated-dependencies:
- dependency-name: spring-io/spring-doc-actions
  dependency-version: 0.0.20
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

Diff for: .github/workflows/update-antora-ui-spring.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Update on docs-build
     steps:
-      - uses: spring-io/spring-doc-actions/update-antora-spring-ui@c2038265125ec6f305a4a041d892ee44c156a754
+      - uses: spring-io/spring-doc-actions/update-antora-spring-ui@e28269199d1d27975cf7f65e16d6095c555b3cd0
         name: Update
         with:
           docs-branch: 'docs-build'