Add build action

.gitea/workflows/pull_request.yaml

@@ -0,0 +1,16 @@
+name: Terrarium Controller Merge Build
+run_name: Test successful terrarium controller build on merge request
+
+on:
+  pull_request:
+    types: [opened, reopened, edited, review_requested, synchronize]
+
+jobs:
+  Build:
+    steps:
+      - uses: https://github.com/actions/checkout@v3
+
+      - uses: https://github.com/dtolnay/rust-toolchain@stable
+
+      - name: Build
+        run: cargo build