Bump drupal/core-recommended from 9.3.12 to 9.3.15

Bumps [drupal/core-recommended](https://github.com/drupal/core-recommended) from 9.3.12 to 9.3.15.
- [Release notes](https://github.com/drupal/core-recommended/releases)
- [Commits](drupal/core-recommended@9.3.12...9.3.15)

---
updated-dependencies:
- dependency-name: drupal/core-recommended
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]