Merge pull request #23 from apple/github-actions-support

[CI] Add support for GitHub Actions

Author: lorentey

.github/workflows/pull_request.yml

@@ -0,0 +1,18 @@
+name: Pull request
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+
+jobs:
+  tests:
+    name: Test
+    uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@main
+  soundness:
+    name: Soundness
+    uses: swiftlang/github-workflows/.github/workflows/soundness.yml@main
+    with:
+      license_header_check_project_name: "Swift Collections"
+      license_header_check_enabled: false
+      unacceptable_language_check_enabled: false
+      format_check_enabled: false