Work around clang-format bug. (#864)

clang-format doesn't deal with missing newlines in some places well:
it inserts them, but not in all the places it needs to, so we end up
in a situation where running it multiple times produces different
output than running it once.

Work around by just manually inserting a newline.

Author: bzbarsky-apple

src-electron/generator/matter/darwin/Framework/CHIP/templates/helper.js

@@ -627,7 +627,7 @@ async function availability(clusterName, options) {
       );
       return `API_AVAILABLE(${availabilityStrings.join(
         ', '
-      )}) MTR_NEWLY_DEPRECATED("${options.hash.deprecationMessage}")`;
+      )})\nMTR_NEWLY_DEPRECATED("${options.hash.deprecationMessage}")`;
     }
     return `MTR_NEWLY_DEPRECATED("${options.hash.deprecationMessage}")`;
   }