Bump io.prometheus:client_java from 1.3.8 to 1.3.9 (#349)

Bumps [io.prometheus:client_java](https://github.com/prometheus/client_java) from 1.3.8 to 1.3.9.
- [Release notes](https://github.com/prometheus/client_java/releases)
- [Commits](prometheus/client_java@v1.3.8...v1.3.9)

---
updated-dependencies:
- dependency-name: io.prometheus:client_java
  dependency-version: 1.3.9
  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>

Author: dependabot[bot]