Eclipse JGit: Java implementation of Git 4.5.5

Fixes

• [Security fix] Fix that AdvertiseRefsHook was not called for git-upload-pack in protocol v0 stateless transports, meaning that in Gerrit using AdvertiseRefsHook for validation wants were not validated and a user could fetch anything that is pointed to by any ref (using fetch-by-sha1), as long as they could guess the object name.
• Retry stale file handles on .git/config file to prevent stale file handle exceptions on NFS

Build and Release Engineering

• Replace Findbugs with Spotbugs