[CORD-772] Example UI Extension update for platform install

Change-Id: I673869b28401d9c5321320ed2b69a282578d0e9f
diff --git a/gulp_tasks/misc.js b/gulp_tasks/misc.js
index d766d14..d1e70ec 100755
--- a/gulp_tasks/misc.js
+++ b/gulp_tasks/misc.js
@@ -12,7 +12,7 @@
 gulp.task('other', other);
 
 function clean() {
-  return del([conf.paths.dist, conf.paths.tmp]);
+  return del([`${conf.paths.dist}/*`, conf.paths.tmp]);
 }
 
 function other() {