buildbot exception in on flink-docs-release-0.10

[buildbot]

The Buildbot has detected a build exception on builder flink-docs-release-0.10 
while building . Full details are available at:
    https://ci.apache.org/builders/flink-docs-release-0.10/builds/114

Buildbot URL: https://ci.apache.org/

Buildslave for this Build: lares_ubuntu

Build Reason: forced: by IRC user <mxm_> on channel #flink-testing: please build
Build Source Stamp: HEAD
Blamelist: 

BUILD FAILED: exception git

Sincerely,
 -The Buildbot