Upgrade bazlets to latest stable-3.1
Upgrade bazlets to latest stable-3.1

To use the now mandatory https protocol for MAVEN_CENTRAL.

Bug: Issue 12170
Change-Id: I8410e27c05a3911e00a3300dba020dc51e092288

GerritCodeReview/plugins_serviceuser,GerritCodeReview/plugins_serviceuser,GerritCodeReview/plugins_serviceuser,GerritCodeReview/plugins_serviceuser,GerritCodeReview/plugins_serviceuser