Fix remaining CI failures after Go 1.12.1 Upgrade

[hanshasselberg]

The changes in build-support have been made by @mkeeler. Plus this change: go mod edit -require github.com/hashicorp/mdns@v1.0.1 to pull in the version that builds for arm64.

[mkeeler]

LGTM

[pearkes]

It looks like we have a consistently failing tests and some go vet issues after the upgrade based on CI. TestGoDiscoverRegistration in particular. Think we just need to upgrade that to support the mdns provider.

[jefferai]

go mod edit -require github.com/hashicorp/mdns@v1.0.1

It's fine in this case, but generally speaking you don't want to do this. Use go get github.com/hashicorp/mdns@v1.0.1 instead, and any time you make changes follow with go mod tidy, then inspect before committing.

[mkeeler]

go mod edit -require github.com/hashicorp/mdns@v1.0.1

It's fine in this case, but generally speaking you don't want to do this. Use go get github.com/hashicorp/mdns@v1.0.1 instead, and any time you make changes follow with go mod tidy, then inspect before committing.

Thats totally fine by me but why is go get preferred over go mod edit?

[jefferai]

From the help output:

The -require=path@version and -droprequire=path flags add and drop a requirement on the given module path and version. Note that -require overrides any existing requirements on path. These flags are mainly for tools that understand the module graph. Users should prefer 'go get path@version' or 'go get path@none', which make other go.mod adjustments as needed to satisfy constraints imposed by other modules.

[mkeeler]

Just a couple minor requests.

[mkeeler]