Clean up bad layout files in zuul tests

Clean up the bad layout files in the zuul tests by removing a redundant
file (bad_pipeline and bad_pipeline1.yaml were identical). Annotate the
reason the layout is bad in each file. Finally remove a redundant swift
section. Both bad switf sections were failing for the same reason, a
missing name entry.

Change-Id: I0fd09da1fb0ec7443fa7d12a3b31809546a01afd
diff --git a/tests/fixtures/layouts/bad_merge_failure.yaml b/tests/fixtures/layouts/bad_merge_failure.yaml
index 313d23b..fc6854e 100644
--- a/tests/fixtures/layouts/bad_merge_failure.yaml
+++ b/tests/fixtures/layouts/bad_merge_failure.yaml
@@ -10,6 +10,7 @@
     failure:
       gerrit:
         verified: -1
+    # merge-failure-message needs a string.
     merge-failure-message:
 
   - name: gate