Fix "html scanner" tests when run in isolation

...and sometimes when running all tests, seemingly

packages/minifiers/package.js

@@ -12,7 +12,7 @@ Npm.depends({
 Npm.strip({
   "uglify-js": ["test/"],
   "css-parse": ["test/"],
-  "css-stringify": ["test/"],
+  "css-stringify": ["test/"]
 });
 
 Package.onUse(function (api) {

packages/templating/package.js

@@ -48,6 +48,7 @@ Package.onTest(function (api) {
   api.use(['test-helpers', 'session', 'tracker',
            'minimongo'], 'client');
   api.use('spacebars-compiler');
+  api.use('minifiers'); // ensure compiler output is beautified
 
   api.addFiles([
     'plugin/html_scanner.js',