Release Zulip Server 6.0-rc1.

docs/overview/changelog.md

@@ -5,7 +5,7 @@ This page the release history for the Zulip server. See also the
 
 ## Zulip 6.x series
 
-### 6.0 -- unreleased
+### 6.0-rc1 -- 2022-11-02
 
 This section is an incomplete draft of the release notes for the next
 major release, and is only updated occasionally. See the [commit

version.py

@@ -1,6 +1,6 @@
 import os
 
-ZULIP_VERSION = "6.0-dev+git"
+ZULIP_VERSION = "6.0-rc1"
 
 # Add information on number of commits and commit hash to version, if available
 zulip_git_version_file = os.path.join(