slaprunner: check htpasswd file exists before removal

slapos/runner/utils.py

@@ -84,6 +84,7 @@ def saveSession(config, account):
     # Htpasswd file for cloud9
     # XXX Cedric Le N order of account list values suppose to be fixed
     # Remove former file to avoid aoutdated accounts
+    if os.path.exists(htpasswdfile):
       os.remove(htpasswdfile)
     passwd = HtpasswdFile(htpasswdfile, create=True)
     passwd.update(account[0], account[1])