remove clouds.yaml in clean.sh

devstack failed to install because glance:
Could not determine a suitable URL for the plugin

patch I618ea8e27b49af360c905df85af06d9b1eef8407 tries
to fix this problem, but with a wrong way because path is not
correct, the clouds.yaml is not under /path/to/devstack/~/.config/openstack/
but ~/.config/openstack.

patch I8af6bd465f74099c560dddba6b5221dd79cbc965 tries to
fix this problem, but with a worng way to specify the path,
~$STACK_USER/.config/openstack/clouds.yaml will not expand with
a variable, only const string can.

$ whoami
zqfan
$ touch ~/.config/openstack/clouds.yaml
$ export STACK_USER=zqfan
$ rm -rf ~$STACK_USER/.config/openstack/clouds.yaml
$ ls ~/.config/openstack/
clouds.yaml

Change-Id: I549817d2f4638be615991c1726b39d270ba71357
ref: I618ea8e27b49af360c905df85af06d9b1eef8407
diff --git a/clean.sh b/clean.sh
index b18f28e..1176134 100755
--- a/clean.sh
+++ b/clean.sh
@@ -137,9 +137,10 @@
 FILES_TO_CLEAN=".localrc.auto .localrc.password "
 FILES_TO_CLEAN+="docs/files docs/html shocco/ "
 FILES_TO_CLEAN+="stack-screenrc test*.conf* test.ini* "
-FILES_TO_CLEAN+=".stackenv .prereqs "
-FILES_TO_CLEAN+="~/.config/openstack"
+FILES_TO_CLEAN+=".stackenv .prereqs"
 
 for file in $FILES_TO_CLEAN; do
     rm -rf $TOP_DIR/$file
 done
+
+rm -rf ~/.config/openstack