ref(deno): Update deno integrations to avoid setupOnce

[mydea]

Where possible, we should use the new processEvent and/or setup hooks of the integrations, instead of setupOnce. This updates this for the deno integrations.

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser (incl. Tracing, Replay, Feedback) - Webpack (gzipped)	75.04 KB (0%)
@sentry/browser (incl. Tracing, Replay) - Webpack (gzipped)	66.38 KB (0%)
@sentry/browser (incl. Tracing, Replay) - Webpack with treeshaking flags (gzipped)	59.99 KB (0%)
@sentry/browser (incl. Tracing) - Webpack (gzipped)	31.13 KB (0%)
@sentry/browser (incl. Feedback) - Webpack (gzipped)	29.74 KB (0%)
@sentry/browser - Webpack (gzipped)	21.39 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback) - ES6 CDN Bundle (gzipped)	71.61 KB (+0.02% 🔺)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (gzipped)	63.33 KB (+0.02% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (gzipped)	29.67 KB (+0.03% 🔺)
@sentry/browser - ES6 CDN Bundle (gzipped)	21.72 KB (+0.05% 🔺)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (minified & uncompressed)	199.58 KB (+0.03% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (minified & uncompressed)	89.94 KB (+0.06% 🔺)
@sentry/browser - ES6 CDN Bundle (minified & uncompressed)	64.92 KB (+0.08% 🔺)
@sentry/browser (incl. Tracing) - ES5 CDN Bundle (gzipped)	32.34 KB (+0.03% 🔺)
@sentry/react (incl. Tracing, Replay) - Webpack (gzipped)	66.75 KB (0%)
@sentry/react - Webpack (gzipped)	21.44 KB (0%)
@sentry/nextjs Client (incl. Tracing, Replay) - Webpack (gzipped)	83.48 KB (0%)
@sentry/nextjs Client - Webpack (gzipped)	48.23 KB (0%)
@sentry-internal/feedback - Webpack (gzipped)	16.19 KB (0%)

[timfish]

If there any reason we can't make setupOnce optional so that we don't need to include the empty method?

Adding setup has broken forwards compatibility anyway since older SDKs wont call setup or the other new methods.

[mydea]

only because the current Integration type has setupOnce being required, so in theory anybody importing one of these integrations could depend on this function existing (it's rather an edge case, but...)

Overall the "solution" for this should be #9818, which makes this optional (*for now it just provides a default empty setupOnce function).