fix: correctly support multiValueHeaders in go functions during development

[danez]

Summary

Fixes #4575

multiValueHeaders was simply not forwarded from the response of the go function

Side note: rust functions have the same problem, but I did not want to fix this in one PR. Should I apply this fix also to rust?

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[github-actions]

📊 Benchmark results

Comparing with 441d7ff

Package size: 287 MB

(no change)

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└───┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴──>
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Legend

• T-30 (441d7ff): 287 MB
• T-29 (5d5aeae): 287 MB
• T-28 (9b70a1b): 287 MB
• T-27 (ae382d1): 287 MB
• T-26 (0009146): 287 MB
• T-25 (5f217e5): 287 MB
• T-24 (ad23be3): 286 MB
• T-23 (7bdf548): 286 MB
• T-22 (a139ef1): 286 MB
• T-21 (a4c9dbb): 286 MB
• T-20 (b6d76e8): 286 MB
• T-19 (0845e80): 286 MB
• T-18 (3e43d9a): 286 MB
• T-17 (d017df9): 286 MB
• T-16 (216631a): 286 MB
• T-15 (f5b1ab5): 286 MB
• T-14 (ae4d49b): 286 MB
• T-13 (7c5156d): 286 MB
• T-12 (c6fd8a6): 286 MB
• T-11 (9faabf3): 286 MB
• T-10 (1956c51): 285 MB
• T-9 (e3ffcb1): 285 MB
• T-8 (a31d411): 285 MB
• T-7 (d35f7e0): 285 MB
• T-6 (f4ee7a4): 285 MB
• T-5 (73b2d6a): 285 MB
• T-4 (01d8217): 285 MB
• T-3 (7b6ffca): 285 MB
• T-2 (b844274): 285 MB
• T-1 (4f6f577): 274 MB
• T (current commit): 287 MB

[danez]

🤔 The automation doesn't seem to be sure if I am a contributor 😁

[eduardoboucas]

Great work!

Also, to your question:

Side note: rust functions have the same problem, but I did not want to fix this in one PR. Should I apply this fix also to rust?

Yes, please! 🙌🏻

[eduardoboucas]

🚀