Use git clone bare instead of mirror

mirror with refs explicit isn't supported in newer git version.  bare is want is desired, that is don't get upstream remotes.

 patch by Mick Semb Wever; reviewed by Brandon Williams

ccmlib/repository.py

@@ -164,9 +164,7 @@ def clone_development(git_repo, version, verbose=False, alias=False):
         if not os.path.exists(local_git_cache):
             common.info("Cloning Cassandra...")
             process = subprocess.Popen(
-                ['git', 'clone', '--mirror',
-                 '-c remote.origin.fetch=+refs/heads/*:refs/heads/*',
-                 '-c remote.origin.fetch=+refs/tags/*:refs/tags/*',
+                ['git', 'clone', '--bare',
                  git_repo, local_git_cache],
                 cwd=__get_dir(), stdout=subprocess.PIPE, stderr=subprocess.PIPE)
             out, _, _ = log_info(process, logger)