docs: add release notes

Author: ffranr

docs/release-notes/release-notes-0.7.0.md

@@ -43,6 +43,7 @@
    - https://github.com/lightninglabs/taproot-assets/pull/1554
    - https://github.com/lightninglabs/taproot-assets/pull/1587
    - https://github.com/lightninglabs/taproot-assets/pull/1675
+   - https://github.com/lightninglabs/taproot-assets/pull/1674
 
 - A new [address version 2 was introduced that supports grouped assets and
   custom (sender-defined)