Merge branch 'stable-3.7' into stable-3.8
* stable-3.7:
Remove redundant format calls in log calls
Add put method to create/update global-refdb entry
Add happy path test for BatchRefUpdateValidator
Remove Maven legacy pom.xml
Return immediately if local ref update fails
Remove references to Zookeeper in logs
Squash filter/findFirst/isPresent into anyMatch
Fix typo in private method
Bump Gerrit and module to v3.6.6
Bump Gerrit and module to v3.5.6
Change-Id: I930b79a021e409983e55d5184c9974515fae323b
