make git show not display a diff

if the top commit includes actual content, this was being displayed
in the devstack log, which was just confusing. --quiet suppresses
this.

Change-Id: Id52604d3b2b9a1372746120cb5d8d741c35576b7
diff --git a/functions b/functions
index 209f13c..d590ac5 100644
--- a/functions
+++ b/functions
@@ -556,7 +556,7 @@
         echo "Running in offline mode, clones already exist"
         # print out the results so we know what change was used in the logs
         cd $GIT_DEST
-        git show --oneline
+        git show --oneline --quiet
         return
     fi
 
@@ -604,7 +604,7 @@
 
     # print out the results so we know what change was used in the logs
     cd $GIT_DEST
-    git show --oneline
+    git show --oneline --quiet
 }