Update docs to reflect command is supported on 2020 (#13702)

Author: jessehouwing

docs/authoring/commands.md

@@ -440,7 +440,7 @@ To invoke a logging command, simply emit the command via standard output. For ex
                     Update release name for current release.<br>
                     <b>Example:</b> <br>
                     <code>##vso[release.updatereleasename]my-new-release-name</code><br>
-                    This command is not supported in Azure DevOps Server(TFS).
+                    This command is not supported in Azure DevOps Server (TFS) 2019 and below.
                 </p>
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