fix: use ubuntu-latest runner for tofu-checks (opentofu image lacks node for actions/checkout)

.gitea/workflows/pr-checks.yaml

@@ -7,13 +7,20 @@ on:
 
 jobs:
   tofu-checks:
+    name: OpenTofu Validate & Policy
     runs-on: ubuntu-latest
-    container:
-      image: ghcr.io/opentofu/opentofu:1.11
     steps:
       - name: Checkout
         uses: actions/checkout@v4
 
+      - name: Install OpenTofu
+        run: |
+          wget -q https://github.com/opentofu/opentofu/releases/download/v1.11.0/tofu_1.11.0_linux_amd64.tar.gz
+          tar xzf tofu_1.11.0_linux_amd64.tar.gz tofu
+          mv tofu /usr/local/bin/
+          rm tofu_1.11.0_linux_amd64.tar.gz
+          tofu --version
+
       - name: Install conftest
         run: |
           wget -q https://github.com/open-policy-agent/conftest/releases/download/v0.66.0/conftest_0.66.0_Linux_x86_64.tar.gz