Update the cache use in our workflows (#653)

<!-- Provide a brief summary of your changes -->

## Motivation and Context
<!-- Why is this change needed? What problem does it solve? -->
While debugging
https://github.com/modelcontextprotocol/registry/pull/631 noticed the
cache was weirdly implemented, so the following PR updates the caching
strategy across a few of our CI workflows.
- Replaced manual actions/cache with the built-in `cache: true` of
setup-go
- Switched from manual golangci-lint installation to their official
golangci-lint-action
- Removed redundant go mod download commands
- Added cache to the deployment pipeline for both staging and production
(we should see faster Pulumi deployments)
- Same for the release workflow so hopefully faster release builds

## How Has This Been Tested?
<!-- Have you tested this in a real application? Which scenarios were
tested? -->

## Breaking Changes
<!-- Will users need to update their code or configurations? -->
No
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update

## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [ ] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [ ] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed

## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->

Signed-off-by: Radoslav Dimitrov <radoslav@stacklok.com>

.github/workflows/deploy.yml

@@ -69,6 +69,7 @@ jobs:
         uses: actions/setup-go@44694675825211faa026b3c33043df3e48a5fa00
         with:
           go-version-file: 'go.mod'
+          cache: true
 
       - name: Setup Pulumi
         uses: pulumi/actions@d7ceb0215da5a14ec84f50b703365ddf0194a9c8
@@ -110,6 +111,7 @@ jobs:
         uses: actions/setup-go@44694675825211faa026b3c33043df3e48a5fa00
         with:
           go-version-file: 'go.mod'
+          cache: true
 
       - name: Setup Pulumi
         uses: pulumi/actions@d7ceb0215da5a14ec84f50b703365ddf0194a9c8