fix: remove unnecessary GOARCH env in Dockerfile

[tydra-wang]

What this PR does / why we need it:

When I build kic in arm64 environment, I found GOARCH hard coded in Dockerfile.

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All committers have signed the CLA.

[codecov]

Codecov Report

Merging #1046 (5ca1c95) into main (1033dee) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1046   +/-   ##
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  Coverage   49.42%   49.42%           
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  Files          32       32           
  Lines        3207     3207           
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  Hits         1585     1585           
  Misses       1492     1492           
  Partials      130      130           

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[shaneutt]

Thanks for the contribution! 🥳

The upstream image already supports a variety of platforms, so I can appreciate and understand wanting to remove this declaration to make it easier to build for other platforms, so from a purely functional perspective this LGTM.

However please do note that amd64 is the only platform we support at the moment and we're not yet ready to support other platforms due to testing and other logistics.

If you're interested in getting support for ARM I would recommend subscribing to #1019 and contributing there with context about your use case(s) to help drive that forward.

[rainest]

To confirm, @shaneutt your comment is effectively "we'll remove the restriction, but be aware that we don't actually support anything else and you're on your own if it breaks"?

I think that's the case, and don't see a reason we need to keep this, since we build images on amd64 machines and Go will default to that.

[shaneutt]

To confirm, @shaneutt your comment is effectively "we'll remove the restriction, but be aware that we don't actually support anything else and you're on your own if it breaks"?

That's right.