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

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