Don't attempt to open an interactive editor

Merging with git can cause git to want to pop you into an editor. That's
not cool in a script. Supply --no-edit to cause the commit to just work.

Change-Id: Ic70d74c28d1ca16ae21b2a6c141b26d4e68b21f0

modules/jenkins/files/slave_scripts/merge_tags.sh

@@ -23,7 +23,7 @@ then
     git review -s
     git checkout master
     git reset --hard origin/master
-    git merge -s ours $TAG
+    git merge --no-edit -s ours $TAG
     # Get a Change-Id
     GIT_EDITOR=true git commit --amend
     git review -R -t merge/release-tag