feat: test STACKIT runner (#78)

Signed-off-by: marcel.henselin <marcel.henselin@stackit.cloud>

## Description

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relates to #1234

## Checklist

- [ ] Issue was linked above
- [ ] Code format was applied: `make fmt`
- [ ] Examples were added / adjusted (see `examples/` directory)
- [x] Docs are up-to-date: `make generate-docs` (will be checked by CI)
- [ ] Unit tests got implemented or updated
- [ ] Acceptance tests got implemented or updated (see e.g. [here](f5f99d1709/stackit/internal/services/dns/dns_acc_test.go))
- [x] Unit tests are passing: `make test` (will be checked by CI)
- [x] No linter issues: `make lint` (will be checked by CI)

Reviewed-on: #78
Co-authored-by: marcel.henselin <marcel.henselin@stackit.cloud>
Co-committed-by: marcel.henselin <marcel.henselin@stackit.cloud>

.github/workflows/ci.yaml

@@ -22,6 +22,39 @@ env:
   CODE_COVERAGE_ARTIFACT_NAME: "code-coverage"
 
 jobs:
+  runner_test:
+    name: "Test STACKIT runner"
+    runs-on: stackit-docker
+    steps:
+      - name: Install needed tools
+        run: |
+          apt-get -y -qq update
+          apt-get -y -qq install jq python3 python3-pip python-is-python3 s3cmd git make wget
+
+      - name: Setup Go
+        uses: actions/setup-go@v6
+        with:
+          go-version: ${{ env.GO_VERSION }}
+
+      - name: Install go tools
+        run: |
+          go install golang.org/x/tools/cmd/goimports@latest
+          go install github.com/hashicorp/terraform-plugin-codegen-framework/cmd/tfplugingen-framework@latest
+          go install github.com/hashicorp/terraform-plugin-codegen-openapi/cmd/tfplugingen-openapi@latest
+
+      - name: Setup JAVA
+        uses: actions/setup-java@v5
+        with:
+          distribution: 'temurin' # See 'Supported distributions' for available options
+          java-version: '21'
+
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Run build pkg directory
+        run: |
+          go run cmd/main.go build
+
   publish_test:
     name: "Test readiness for publishing provider"
     needs: config