Compress release with UPX

[dustin-decker]

Description:

Compresses the release binary with UPX. On my machine, I had a 48% compression ratio!
I've omitted Darwin because we've seen issues with OSX signing on our Enterprise build when using UPX.

In this PR i've updated the UPX command to allow failure.
I've also changed CI to use the gorelease-pro distribution. That will allow us to parallelize builds later on as well.

Checklist:

• Tests passing (make test-community)?
• Lint passing (make lint this requires golangci-lint)?

[zricethezav]

@dustin-decker I like the UPX optimization. Couple of comments:

1. Are we sure this works for windows? The UPX readme suggests that windows arm64 isn't supported.
2. I find this oneliner to be a little hard on the eyes. WDYT about specifically defining a darwin build like:

builds:
  - id: trufflehog-upx
    binary: trufflehog
    ldflags:
      - -X 'github.com/trufflesecurity/trufflehog/v3/pkg/version.BuildVersion={{ .Version }}'
    env: [CGO_ENABLED=0]
    goos:
    - linux
    goarch:
    - amd64
    - arm64
    hooks:
      post:
        - upx "{{ .Path }}"
  - id: trufflehog
    binary: trufflehog
    ldflags:
      - -X 'github.com/trufflesecurity/trufflehog/v3/pkg/version.BuildVersion={{ .Version }}'
    env: [CGO_ENABLED=0]
    goos:
    - darwin
    - windows
    goarch:
    - amd64
    - arm64

This could be split out differently too like on OS rather than upx enabled - trufflehog-linux, trufflehog-darwin, trufflehog-windows.