docs: Update dependencies.md

docs/dev/dependencies.md

@@ -16,33 +16,15 @@ If you need support for [libvirt destroy](libvirt/README.md#cleanup), you should
 
 We follow a hard flattening approach; i.e. direct and inherited dependencies are installed in the base `vendor/`.
 
-Dependencies are managed with [dep](https://golang.github.io/dep/) but committed directly to the repository. If you don't have dep, install the latest release from [Installation](https://golang.github.io/dep/docs/installation.html) link.
+Dependencies are managed with [Go Modules](https://github.com/golang/go/wiki/Modules) but committed directly to the repository.
 
-We require at least following version for dep:
+We require at least Go 1.13.
 
-```console
-$ dep version
-dep:
- version     : v0.5.0
- build date  : 2018-07-26
- git hash    : 224a564
- go version  : go1.10.3
-```
+- Add or update a dependency with `go get <dependency>@<version>`.
+- If you want to use a fork of a project or ensure that a dependency is not updated even when another dependency requires a newer version of it, manually add a [replace directive in the go.mod file](https://github.com/golang/go/wiki/Modules#when-should-i-use-the-replace-directive). 
+- Run `go mod tidy` to tidy `go.mod` and update `go.sum`, then commit the changes.
+- Run `go mod vendor` to re-vendor and then commit updated vendored code separately.
 
-To add a new dependency:
-
-- Edit the `Gopkg.toml` file to add your dependency.
-- Ensure you add a `version` field for the tag or the `revision` field for commit id you want to pin to.
-- Revendor the dependencies:
-
-```sh
-dep ensure
-```
-
-This [guide](https://golang.github.io/dep/docs/daily-dep.html) is a great source to learn more about using `dep`.
+This [guide](https://github.com/golang/go/wiki/Modules#how-to-use-modules) is a great source to learn more about using `go mod`.
 
 For the sake of your fellow reviewers, commit vendored code separately from any other changes.
-
-## Tests
-
-See [tests/README.md](../../tests/README.md).