help docs: Fix a wrong link in create-a-stream doc
help docs: Fix a wrong link in create-a-stream doc

Discussion:
  https://chat.zulip.org/#narrow/stream/19-documentation/topic/Wrong.20link.20.28stream.20creation.29/near/1380786

zulip/zulip,rht/zulip,zulip/zulip,andersk/zulip,rht/zulip,zulip/zulip,zulip/zulip,rht/zulip,andersk/zulip,rht/zulip,andersk/zulip,andersk/zulip,andersk/zulip,andersk/zulip,rht/zulip,zulip/zulip,rht/zulip,zulip/zulip,rht/zulip,andersk/zulip,zulip/zulip