Consume the dep binary from the Paketo dep-server

[fg-j]

Per paketo-buildpacks/dep-server#45, we should start consuming the dep dependency from the dep-server (See https://api.deps.paketo.io/v1/dependency?name=dep for dependency metadata) instead of the https://buildpacks.cloudfoundry.org/dependencies/dep/... location we currently get the dependencies from.

This will make the dependency publishing/consumption process more transparent than the process we use for the dependencies available via the dependency-builds pipeline.

We have already done this switch-over in the Node Engine and Yarn Buildpacks. The outline of what this work will entail can be found in the dep-server issue linked at the top.

[fg-j]

This is blocked until the dep server supports the dep dependency. Currently, hitting the dependency API endpoint (https://api.deps.paketo.io/v1/dependency?name=dep) returns an error.

[sophiewigmore]

@fg-j I don't actually think that the dep dependency is in the dependency builds pipeline either (probably because it's deprecated by Golang in favour of go modules). It looks like the version of the dependency in the buildpack.toml has not been updated in 12 months, and was last updated by hand. We probably don't need this issue, since we have no reason to poll for new dep versions in the dep-server

[ryanmoran]

The golang/dep repo has been archived and there will be no future releases. Support for dep only exists as a legacy support mechanism and will be removed once go.mod becomes the only package management mechanism.

[fg-j]

In that case, it sounds like we don't actually care to consume dep from the dep-server. Closing for now. Feel free to re-open if I've got the wrong idea here.