Bump buildpacks/maven/test-apps/heroku-java-getting-started (#754)

Bumps [buildpacks/maven/test-apps/heroku-java-getting-started](https://github.com/heroku/java-getting-started) from `28a40a6` to `75e5385`.
- [Commits](heroku/java-getting-started@28a40a6...75e5385)

---
updated-dependencies:
- dependency-name: buildpacks/maven/test-apps/heroku-java-getting-started
  dependency-type: direct:production
...

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