Add a GitHub Action

.github/workflows/ci.yaml

@@ -0,0 +1,38 @@
+name: CI
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  cargo_build:
+    name: "cargo build"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+      - run: cargo build --bin rust_python_linter --release
+
+  cargo_fmt:
+    name: "cargo fmt"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+      - run: cargo fmt --check
+
+  cargo_clippy:
+    name: "cargo clippy"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+      - run: cargo clippy -- -D warnings