CI fails to build FIPS compliant images using art container builder.
toolchain directive in the go mod makes go search for that specific version,
if its not in the system, it will download it from official sources,
forcing the builder  to use upstream golang.

> Starting in Go 1.21, when you need a newer Go toolchain, the go command downloads that for you too. This functionality is like Node's nvm or Rust's rustup, but built in to the core go command instead of being a separate tool.
from https://go.dev/blog/toolchain

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