moveit_pr2: 0.5.1-0 in 'hydro/release.yaml' [bloom]

Increasing version of package(s) in repository `moveit_pr2`:
- previous version: `0.5.0-0`
- new version: `0.5.1-0`
- distro file: `hydro/release.yaml`
- bloom version: `0.4.2`