Switch build process to goreleaser

[dduportal]

This PR aims at switching the build process from tedious shell scripting to GoReleaser.
It is a foundational work for the futures PR about #154.

The scope of the PR is to provide a replacement "as it", without enabling all the powerful feature of goreleaser yet, which means:

• Only build the binaries with the same name as before
• No release, no binary checksum, no changelog, no homebrew support managed by goreleaser

Please note that command make build is now building all of the binaries:

• The rationale is to use build matrix instead of 1 build per couple GOOS + GOARCH as in https://github.com/garethjevans/inspect/blob/main/.goreleaser.yml#L9 (ldflags are not duplicated, etc.).
• The overhead is ~ 0.4s on my machine (MBP Core i7 2,6 Ghz, 16 Go, NVMe): Running 15 times the build has a median build time of 4.2s (max 4.8, min 3.9) while it was 3.8s before goreleaser (max 4.4 min 3.6).
• The difference with make build.all for now is that make build is aimed at development, so it uses the --snapshot flag for goreleaser.

[olblak]

Thanks for this PR, I can't wait to use more goreleaser