YARN-11173. remove redeclaration of os-maven-plugin.version from yarn-csi (#4417)
This is a followup to HADOOP-18275 and its upgrade of os-maven-plugin.version
When that change is merged in, this MUST follow it.
Contributed by Steve Loughran
Change-Id: I61d087041561eeb8c9c42b5b7d8f0bb63f296b15