fix(core): Use last error for ignoreErrors check

[lobsterkatie]

This fixes a helper function used in our implementation of ignoreErrors so that in the case of linked errors, it filters on the primary error (the one directly caught by captureException) rather than the error in the primary error's cause property. See #8079 for screenshots and a more detailed explanation.

Fixes #8079.

[github-actions]

⚠️ This PR is opened against master. You probably want to open it against develop.

[Lms24]

LGTM, thanks for fixing this!

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	21.02 KB (+0.04% 🔺)
@sentry/browser - ES5 CDN Bundle (minified)	65.62 KB (+0.01% 🔺)
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	19.56 KB (+0.07% 🔺)
@sentry/browser - ES6 CDN Bundle (minified)	58.09 KB (+0.01% 🔺)
@sentry/browser - Webpack (gzipped + minified)	21.17 KB (+0.05% 🔺)
@sentry/browser - Webpack (minified)	69.04 KB (+0.01% 🔺)
@sentry/react - Webpack (gzipped + minified)	21.19 KB (+0.04% 🔺)
@sentry/nextjs Client - Webpack (gzipped + minified)	49.1 KB (-0.01% 🔽)
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	28.64 KB (+0.03% 🔺)
@sentry/browser + @sentry/tracing - ES6 CDN Bundle (gzipped + minified)	26.88 KB (+0.06% 🔺)
@sentry/replay ES6 CDN Bundle (gzipped + minified)	47.35 KB (+0.01% 🔺)
@sentry/replay - Webpack (gzipped + minified)	41.13 KB (0%)
@sentry/browser + @sentry/tracing + @sentry/replay - ES6 CDN Bundle (gzipped + minified)	66.31 KB (+0.02% 🔺)
@sentry/browser + @sentry/replay - ES6 CDN Bundle (gzipped + minified)	59.19 KB (+0.02% 🔺)