Tweak end2end formatting

templates/test/core/end2end/end2end_nosec_tests.c.template

 %YAML 1.2
 --- |
-  <%namespace file="end2end_defs.include" import="*"/>
-  ${end2end_selector(k for k, v in core_end2end_tests.iteritems() if not v)}
-
+  <%namespace file="end2end_defs.include" import="*"/>\
+  ${end2end_selector(k for k, v in core_end2end_tests.iteritems() if not v)}\

templates/test/core/end2end/end2end_tests.c.template

 %YAML 1.2
 --- |
-  <%namespace file="end2end_defs.include" import="*"/>
-  ${end2end_selector(core_end2end_tests.keys())}
-
+  <%namespace file="end2end_defs.include" import="*"/>\
+  ${end2end_selector(core_end2end_tests.keys())}\

test/core/end2end/end2end_nosec_tests.c

 
-
 /*
  *
  * Copyright 2015-2016, Google Inc.
@@ -263,4 +262,3 @@ void grpc_end2end_tests(int argc, char **argv,
     abort();
   }
 }
-

test/core/end2end/end2end_tests.c

 
-
 /*
  *
  * Copyright 2015-2016, Google Inc.
@@ -269,4 +268,3 @@ void grpc_end2end_tests(int argc, char **argv,
     abort();
   }
 }
-