feat: add build job

- add build job that runs `make plan`
- add deploy job that runs `make apply`
- ensure make-plan also runs init target
- enable provider caching
- enable creating client.crt/client.key
- trap EXIT to cleanup temp directory

.gitea/workflows/deploy.yaml

@@ -19,7 +19,15 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Run Terraform Plan
+      - name: Fetch master branch
+        run: |
+          git fetch origin master:master
+
+      - name: Show changed files
+        run: |
+          git diff --name-only master
+
+      - name: Run Terraform Apply
         env:
           VAULT_ROLEID: ${{ secrets.TERRAFORM_INCUS_VAULT_ROLEID }}
         run: |