fix: document security group ID validation issue in changelog and release notes (#776)

Co-authored-by: github-actions[bot] <tfmod442916@users.noreply.github.com>

Author: mawasile

.changes/3.7.2.md

@@ -0,0 +1,5 @@
+## 3.7.2 - 2025-05-16
+
+### 🪲 Fixed
+
+* [#775](https://github.com/microsoft/terraform-provider-power-platform/issues/775) Fixed issue when powerplatform_environment security_group_id validates unknown values incorrectly

.changes/unreleased/fixed-20250516-095207.yaml

@@ -7,6 +7,12 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html),
 and is generated by [Changie](https://github.com/miniscruff/changie).
 
 
+## 3.7.2 - 2025-05-16
+
+### 🪲 Fixed
+
+* [#775](https://github.com/microsoft/terraform-provider-power-platform/issues/775) Fixed issue when powerplatform_environment security_group_id validates unknown values incorrectly
+
 ## 3.7.1 - 2025-05-13
 
 ### 🪲 Fixed