fix: Always use `?` for anonymous function name

[timfish]

Closes #5523

This moves the '?' string to @sentry/utils so it only exists once in the bundle.

[timfish]

Abhi has marked this for v8.0.0 since this is technically a breaking change

[github-actions[bot]]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[AbhiPrasad]

@timfish let's close this to clean up the PRs stream, but we should re-open and merge once v8 is ready.