Update tfc-agent changelog

Author: ryanuber

website/docs/cloud-docs/agents/changelog.mdx

@@ -16,6 +16,12 @@ within each release are categorized into one or more of the following labels:
 Each version below corresponds to a release artifact available for download on
 the official [releases website](https://releases.hashicorp.com/tfc-agent/).
 
+## 1.2.4 (06/21/2022)
+
+BUG FIXES:
+
+* Added support for dangling symlinks with relative targets (#164)
+
 ## 1.2.3 (06/09/2022)
 
 BUG FIXES: