Migrate from Circle CI to GitHub Actions

Since we need to migrate all of our repos to GitHub Actions.

This is based on the config used by our other Rust CNBs.

See:
https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions

The check changelog check was also made consistent with that
used in other Rust repositories (dependencies aren't test-only,
so may sometimes need a changelog entry etc).

.github/workflows/check_changelog.yml

@@ -4,17 +4,20 @@ on:
   pull_request:
     types: [opened, reopened, edited, labeled, unlabeled, synchronize]
 
+permissions:
+  contents: read
+
 jobs:
   check-changelog:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     if: |
       !contains(github.event.pull_request.body, '[skip changelog]') &&
       !contains(github.event.pull_request.body, '[changelog skip]') &&
       !contains(github.event.pull_request.body, '[skip ci]') &&
-      !contains(github.event.pull_request.labels.*.name, 'skip changelog') &&
-      !contains(github.event.pull_request.labels.*.name, 'dependencies')
+      !contains(github.event.pull_request.labels.*.name, 'skip changelog')
     steps:
-      - uses: actions/checkout@v3
+      - name: Checkout
+        uses: actions/checkout@v3
       - name: Check that CHANGELOG is touched
         run: |
           git fetch origin ${{ github.base_ref }} --depth 1 && \

.github/workflows/ci.yml

@@ -0,0 +1,60 @@
+name: CI
+
+on:
+  push:
+    # Avoid duplicate builds on PRs.
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  lint:
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Update Rust toolchain
+        run: rustup update
+      - name: Rust Cache
+        uses: Swatinem/[email protected]
+      - name: Clippy
+        run: cargo clippy --all-targets --locked -- --deny warnings
+      - name: rustfmt
+        run: cargo fmt -- --check
+
+  unit-test:
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Update Rust toolchain
+        run: rustup update
+      - name: Rust Cache
+        uses: Swatinem/[email protected]
+      - name: Run unit tests
+        run: cargo test --locked
+
+  integration-test:
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Install musl-tools
+        run: sudo apt-get install musl-tools --no-install-recommends
+      - name: Update Rust toolchain
+        run: rustup update
+      - name: Install Rust linux-musl target
+        run: rustup target add x86_64-unknown-linux-musl
+      - name: Rust Cache
+        uses: Swatinem/[email protected]
+      - name: Install Pack CLI
+        uses: buildpacks/github-actions/[email protected]
+      - name: Run integration tests
+        # Runs only tests annotated with the `ignore` attribute (which in this repo, are the integration tests).
+        run: cargo test --locked -- --ignored

src/layers/ruby_version_install_layer.rs

@@ -87,8 +87,7 @@ impl Layer for RubyVersionInstallLayer {
         util::download(url.as_ref(), tmp_ruby_tgz.path())
             .map_err(RubyBuildpackError::RubyDownloadError)?;
 
-        util::untar(tmp_ruby_tgz.path(), layer_path)
-            .map_err(RubyBuildpackError::RubyUntarError)?;
+        util::untar(tmp_ruby_tgz.path(), layer_path).map_err(RubyBuildpackError::RubyUntarError)?;
 
         LayerResultBuilder::new(RubyMetadata {
             version: self.version_string(),