DB-802 make.mysql.bash should extract and use the tokudb version as the git...

DB-802 make.mysql.bash should extract and use the tokudb version as the git tag.  there was a broken RE

scripts/common.sh

@@ -163,7 +163,7 @@ function parse_mysqlbuild() {
         fi
 
         # set tag or HEAD
-        if [[ $temp_tokudb_version =~ ^([0-9]+)\\.([0-9]+)\\.([0-9]+) ]] ; then
+        if [[ $temp_tokudb_version =~ ^([0-9]+)\.([0-9]+)\.([0-9]+) ]] ; then
             git_tag=tokudb-$temp_tokudb_version
         else
             git_tag=HEAD