Allowing streams for large uploads to google storage via the GCS client

[k0p04ku]

Testing

I was able to successfully stream a video into GS.

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✅ k0p04ku
❌ kishan.patel

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[cross311]

I think this is a good change, just want to see testing more concrete that it works.

[k0p04ku]

I think this is a good change, just want to see testing more concrete that it works.

I've added an assertion regarding what exactly we're reading and writing into GS.