Fix docs mising Search permission for example. - addition

Gratuitous whiespace change to add:

The

  All users may only view and edit issues, files and messages they create

example was missing the addition of Search permission. The example
predates the existence of the Search permission.

See: https://sourceforge.net/p/roundup/mailman/message/37390174/
for initial report.

Author: rouilj

doc/customizing.txt

@@ -6155,3 +6155,4 @@ rather than requiring a web server restart.
 .. _`directions in the rest interface documentation`: rest.html#enabling-the-rest-api
 .. _`xmlrpc interface documentation`: xmlrpc.html#through-roundup
 .. _`zxcvbn`: https://github.com/dwolfhub/zxcvbn-python
+