DOCSP-43707: 2.21 changes

Author: mcmorisi

config/redirects

@@ -1,8 +1,8 @@
 define: prefix docs/ruby-driver
 define: base https://www.mongodb.com/${prefix}
 define: mongoid_base https://www.mongodb.com/docs/mongoid
-define: versions v1.x v2.0 v2.1 v2.2 v2.3 v2.4 v2.5 v2.6 v2.7 v2.8 v2.9 v2.10 v2.11 v2.12 v2.13 v2.14 v2.15 v2.16 v2.17 v2.18 v2.19 v2.20 master
-symlink: current -> v2.20
+define: versions v1.x v2.0 v2.1 v2.2 v2.3 v2.4 v2.5 v2.6 v2.7 v2.8 v2.9 v2.10 v2.11 v2.12 v2.13 v2.14 v2.15 v2.16 v2.17 v2.18 v2.19 v2.20 v2.21 master
+symlink: current -> v2.21
 
 raw: /${prefix} -> ${base}/current/
 

source/reference/driver-compatibility.txt

@@ -341,7 +341,7 @@ for that Ruby version is deprecated.
      - JRuby 9.2
      - JRuby 9.1
 
-   * - 2.20
+   * - 2.20 to 2.21
      - |checkmark|
      - |checkmark|
      - |checkmark|

source/release-notes.txt

@@ -17,6 +17,19 @@ comprehensive list of changes in each version of the driver and the
 for the complete list of changes, including those internal to the driver and
 its test suite.
 
+.. _release-notes-2.21:
+
+2.21
+====
+
+This release includes the following new features:
+
+- Adds support for the Client-Side Operations Timeout (CSOT) feature, which unifies
+  most timeout-related options under a single ``timeout_ms`` option.
+- Adds support for MongoDB Server version 8.0.
+- Adds support for range v2 queries with Queryable Encryption, including a new ``trim_factor``
+  parameter. For more information about Queryable Encryption, see :manual:`Queryable Encryption </core/queryable-encryption>`
+  in the MongoDB Server manual.
 
 .. _release-notes-2.20:
 
@@ -39,7 +52,6 @@ This release includes the following new features:
 - When attempting a retry of a read or write operation in a sharded topology,
   the retry will be attempted on a different mongos instance, if possible.
 
-
 .. _release-notes-2.19:
 
 2.19