update install instructions to reference provider prerequisites (#638)

Author: jyecusch

docs/get-started/installation.mdx

@@ -12,7 +12,13 @@ Please follow these links to the official installation steps for each.
 - [Git](https://git-scm.com/)
 - [Docker](https://docs.docker.com/get-docker/)
 - [Docker Buildx](https://github.com/docker/buildx/)
-- [Pulumi](https://www.pulumi.com/docs/cli/) _(for deployments, only needed if using the default providers)_
+
+### Deployment Prerequisites
+
+Deployment plugins have their own requirements, please refer to the documentation for the specific deployment provider you want to use.
+
+- [Pulumi Providers](/providers/pulumi#prerequisites)
+- [Terraform Providers](/providers/terraform#prerequisites)
 
 <Note>
   When setting up Docker on Linux be sure to follow the [post-installation