Remove certificate before updating it

Containerized HAProxy always tries to load the SSL certificate; if TLS
is not enabled it will create the file as a directory. This messes up
with the script that actually injects the HAProxy certificate into the
undercloud. To address this, we update that script to take this into
account.

Change-Id: Ifc748648cc0f8caaf5a551fd0bc5724b94f3087d
Closes-Bug: #1728267

puppet/extraconfig/tls/tls-cert-inject.yaml

@@ -52,6 +52,11 @@ resources:
         - name: key_modulus
       config: |
         #!/bin/sh
+        # If the HAProxy container tried to load this, it'll be a directory and
+        # will make this fail.
+        if [ -d ${cert_path} ]; then
+            rm -rf ${cert_path}
+        fi
         cat > ${cert_path} << EOF
         ${cert_chain_content}
         EOF