ci: Add basic workflow to build the repository on Pull Requests

Avoid accidental breakages by checking that changes from new Pull
Requests build correctly. We also run "cargo test", although there's no
test in the project at the moment. We even run Clippy and the format
checker, for good measure.

Signed-off-by: Quentin Monnet <qmo@qmon.net>

Author: qmonnet

.github/workflows/build.yml

@@ -0,0 +1,36 @@
+name: build.yml
+
+on:
+  pull_request: {}
+  push:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: lab
+    steps:
+      - name: Install Rust toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          components: clippy, rustfmt
+
+      - name: Checkout repository
+        uses: actions/checkout@v5
+        with:
+          fetch-depth: 1
+          persist-credentials: false
+
+      - name: Build project
+        run: cargo build
+
+      - name: Run tests
+        run: cargo test
+
+      - name: Run clippy
+        run: cargo clippy -- -D warnings
+
+      - name: Check code formatting
+        run: cargo fmt -- --check