Export `spanStreamingIntegration` from CDN bundles

[Lms24]

Currently, only the browser NPM package exports spanStreamingIntegration. For feature-parity, we should also export the integration from CDN bundles. For simplicity I'd suggest adding it to our .tracing bundles and accepting the size increase.

• Ensure we shim the integration for non-tracing bundles
• Add the export
• Remove the CDN bundle test skip logic in browser integration tests and ensure the tests pass

[linear-code]

JS-2153