ci(v8): Ensure CI runs on v8 & v9 branches (#14604)

[mydea]

In order for us to have size-limit comparison etc, we need to ensure CI runs on v8 & v9 branches too.

Picking this from develop so we also have this on v8 branch!

[github-actions]

size-limit report 📦

Path	Size	% Change	Change
@sentry/browser	23.29 KB	added	added
@sentry/browser - with treeshaking flags	21.96 KB	added	added
@sentry/browser (incl. Tracing)	35.79 KB	added	added
@sentry/browser (incl. Tracing, Replay)	73.01 KB	added	added
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	63.41 KB	added	added
@sentry/browser (incl. Tracing, Replay with Canvas)	77.32 KB	added	added
@sentry/browser (incl. Tracing, Replay, Feedback)	89.81 KB	added	added
@sentry/browser (incl. Feedback)	40.04 KB	added	added
@sentry/browser (incl. sendFeedback)	27.89 KB	added	added
@sentry/browser (incl. FeedbackAsync)	32.68 KB	added	added
@sentry/react	25.96 KB	added	added
@sentry/react (incl. Tracing)	38.6 KB	added	added
@sentry/vue	27.49 KB	added	added
@sentry/vue (incl. Tracing)	37.63 KB	added	added
@sentry/svelte	23.45 KB	added	added
CDN Bundle	24.43 KB	added	added
CDN Bundle (incl. Tracing)	37.46 KB	added	added
CDN Bundle (incl. Tracing, Replay)	72.64 KB	added	added
CDN Bundle (incl. Tracing, Replay, Feedback)	78.01 KB	added	added
CDN Bundle - uncompressed	71.74 KB	added	added
CDN Bundle (incl. Tracing) - uncompressed	111.05 KB	added	added
CDN Bundle (incl. Tracing, Replay) - uncompressed	225.1 KB	added	added
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	238.32 KB	added	added
@sentry/nextjs (client)	38.88 KB	added	added
@sentry/sveltekit (client)	36.29 KB	added	added
@sentry/node	162.52 KB	added	added
@sentry/node - without tracing	98.71 KB	added	added
@sentry/aws-serverless	126.39 KB	added	added