fix session replay crash (highlight#9365)

## Summary

Bring back postcss css parsing which offers better reliability with
inlined stylesheets and better performance.
Fixes replay of a session where the existing CSS parsing of rrweb was
broken.
Incorporates rrweb-io/rrweb#1580 to fix broken
replays due to postcss crash.

## How did you test this change?


https://preview.highlight.io/102751/sessions/35zPFX0OPXs166n5L7m1GEZaqWgL?%7Er_preview=%7B%22action%22%3A%22start%22%2C%22mode%22%3A%22production%22%2C%22region%22%3A%22ewr%22%2C%22variantId%22%3A%2201J8GFGDTWBWCRZZZ7G92P9HJX%22%2C%22variantData%22%3A%22%7B%5C%22type%5C%22%3A%5C%22branch%5C%22%2C%5C%22branch%5C%22%3A%5C%22vadim%2Fsession-troubleshooting%5C%22%2C%5C%22githubOwnerName%5C%22%3A%5C%22highlight%5C%22%2C%5C%22githubRepositoryName%5C%22%3A%5C%22highlight%5C%22%7D%22%7D

fixes replay that is otherwise broken 


https://preview.highlight.io/14083/sessions/77X2eTJA5TIbEydiUytAFmZhJoXn?commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&commentId=90302&page=1&query=viewed_by_anyone%3Dtrue+visited-url%3D%22*6532da*%22&commentId=90302&commentId=90302&%7Er_preview=%7B%22action%22%3A%22start%22%2C%22mode%22%3A%22production%22%2C%22region%22%3A%22ewr%22%2C%22variantId%22%3A%2201J8GFGDTWBWCRZZZ7G92P9HJX%22%2C%22variantData%22%3A%22%7B%5C%22type%5C%22%3A%5C%22branch%5C%22%2C%5C%22branch%5C%22%3A%5C%22vadim%2Fsession-troubleshooting%5C%22%2C%5C%22githubOwnerName%5C%22%3A%5C%22highlight%5C%22%2C%5C%22githubRepositoryName%5C%22%3A%5C%22highlight%5C%22%7D%22%7D

## Are there any deployment considerations?

frontend only

continues to work
![Screenshot from 2024-10-09
17-36-41](https://github.com/user-attachments/assets/f4e6b68a-e993-4292-9d76-0049d3e7b797)


## Does this work require review from our design team?

no

.changeset/shaggy-rabbits-remain.md

@@ -0,0 +1,5 @@
+---
+'highlight.run': minor
+---
+
+update rrweb to use postcss css parser

.reflame.config.jsonc

@@ -374,10 +374,10 @@
       ],
     },
     "highlight.run": {
-      "version": "9.3.4"
+      "version": "9.4.2"
     },
     "@highlight-run/react": {
-      "version": "5.0.4"
+      "version": "6.0.2"
     },
     "antd": {
       "entryPoints": [