nixos/datadog-agent: Note breaking changes in release notes.

nixos/doc/manual/from_md/release-notes/rl-2111.section.xml

@@ -915,7 +915,9 @@ Superuser created successfully.
           <literal>datadog-integrations-core</literal> and
           <literal>datadog-process-agent</literal> packages were
           upgraded from 6.11.2 to 7.30.2, git-2018-09-18 to 7.30.1 and
-          6.11.1 to 7.30.2, respectively. For details, see the
+          6.11.1 to 7.30.2, respectively. As a result
+          <literal>services.datadog-agent</literal> has had breaking
+          changes to the configuration file. For details, see the
           <link xlink:href="https://github.com/DataDog/datadog-agent/blob/main/CHANGELOG.rst">upstream
           changelog</link>.
         </para>

nixos/doc/manual/release-notes/rl-2111.section.md

@@ -265,7 +265,10 @@ To be able to access the web UI this port needs to be opened in the firewall.
 
 - The `todoman` package was upgraded from 3.9.0 to 4.0.0. This introduces breaking changes in the [configuration file](https://todoman.readthedocs.io/en/stable/configure.html#configuration-file) format.
 
-- The `datadog-agent`, `datadog-integrations-core` and `datadog-process-agent` packages were upgraded from 6.11.2 to 7.30.2, git-2018-09-18 to 7.30.1 and 6.11.1 to 7.30.2, respectively. For details, see the [upstream changelog](https://github.com/DataDog/datadog-agent/blob/main/CHANGELOG.rst).
+- The `datadog-agent`, `datadog-integrations-core` and `datadog-process-agent` packages
+  were upgraded from 6.11.2 to 7.30.2, git-2018-09-18 to 7.30.1 and 6.11.1 to 7.30.2,
+  respectively. As a result `services.datadog-agent` has had breaking changes to the
+  configuration file. For details, see the [upstream changelog](https://github.com/DataDog/datadog-agent/blob/main/CHANGELOG.rst).
 
 ## Other Notable Changes {#sec-release-21.11-notable-changes}