Add in 1.8 changelog the backports made in 1.7.30 patch

Author: cderv

news/changelog-1.8.md

@@ -1,5 +1,11 @@
 All changes included in 1.8:
 
+## Regression fixes
+
+- ([#6607](https://github.com/quarto-dev/quarto-cli/issues/6607)): Add missing beamer template update for beamer theme options: `colorthemeoptions`, `fontthemeoptions`, `innerthemeoptions` and `outerthemeoptions`.
+- ([#12625](https://github.com/quarto-dev/quarto-cli/pull/12625)): Fire resize event on window when light/dark toggle is clicked, to tell widgets to resize.
+- ([#12657](https://github.com/quarto-dev/quarto-cli/pull/12657)): Load Giscus in generated script tag, to avoid wrong-theming in Chrome.
+
 ## Formats
 
 ### `html`