zstd PoC

[paulcacheux]

What does this PR do?

Results (go_mod_tidy_check plays the role of a typical retriver here):

step	gzip	zstd
go_deps script step	217sec	120sec
go_deps upload artifact	77sec (pretty surprising)	81sec
artifact size (modcache.tar.XX)	2.06GB	1.9GB
go_mod_tidy_check download artifact	49sec	43sec
go_mod_tidy_check script step	54sec	51sec

the compression is faster, the upload/download is faster (because smaller file), the decompression is theoretically faster

Tradeoff: zstd needs to be installed in all build images (and manually in *_x64 because not available via package manager)

TODO:

• [ ] merge buildimages PR and update tags
• [ ] merge images PR (used by serverless test) and update tags

Motivation

Additional Notes

Possible Drawbacks / Trade-offs

Describe how to test/QA your changes

Reviewer's Checklist

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