Fix a syntax typo

This worked for now, but is SyntaxError in Python 3.9.0a6:

  File "/usr/lib/python3.9/site-packages/ipapython/cookie.py", line 222
    return'/'
         ^
SyntaxError: invalid string prefix

(The Python change might actually be reverted before 3.9 final,
but this can be fixed anyway.)

Reviewed-By: Christian Heimes <cheimes@redhat.com>

ipapython/cookie.py

@@ -219,7 +219,7 @@ class Cookie:
             return '/'
 
         if url_path.count('/') <= 1:
-            return'/'
+            return '/'
 
         return url_path[:url_path.rindex('/')]