docs: add release notes for v6.0.20

Author: github-actions[bot]

release_notes/v6.0.20.md

@@ -0,0 +1,9 @@
+## [6.0.20](https://github.com/NHSDigital/eps-common-workflows/compare/v6.0.19...v6.0.20) (2026-04-30)
+
+
+### Upgrade
+
+* [dependabot] - bump dependabot/fetch-metadata from 3.0.0 to 3.1.0 (#156) ([b4a2329](https://github.com/NHSDigital/eps-common-workflows/commit/b4a2329f8b50118f5ef0d22f3f0db37050f8c617))
+* [dependabot] - bump NHSDigital/eps-copilot-instructions from 1.0.5 to 1.0.6 (#155) ([38c447f](https://github.com/NHSDigital/eps-common-workflows/commit/38c447f0450212b906a8e19d1ed6afebddf0bfe3))
+* [dependabot] - bump NHSDigital/eps-dependabot-approve from 1.0.2 to 1.0.3 (#158) ([2577a3e](https://github.com/NHSDigital/eps-common-workflows/commit/2577a3e29f7d33c1346b6e32f981259916c918c8))
+* [dependabot] - bump NHSDigital/eps-update-devcontainer from 1.0.4 to 1.0.5 (#157) ([9f26a6b](https://github.com/NHSDigital/eps-common-workflows/commit/9f26a6bd41a1acca0e23597f88492577f97c705e))