Add linkage test (#53)

### Motivation

Ensure that we don't accidentally link the full Foundation on Linux, as
we generally only need FoundationEssentials.

### Modifications

Adds a script ensuring that the Configuration module only links
FoundationEssentials on Linux.

### Result

Confidence that we don't accidentally start linking the full Foundation.

### Test Plan

CI.

Author: czechboy0

.github/workflows/main.yml

@@ -54,3 +54,30 @@ jobs:
       windows_6_1_enabled: false
       windows_nightly_next_enabled: false
       windows_nightly_main_enabled: false
+
+  construct-linkage-test-matrix:
+    name: Construct linkage matrix
+    runs-on: ubuntu-latest
+    outputs:
+      integration-test-matrix: '${{ steps.generate-matrix.outputs.integration-test-matrix }}'
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+      - id: generate-matrix
+        run: echo "integration-test-matrix=$(curl -s https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        env:
+          MATRIX_LINUX_SETUP_COMMAND: apt-get update -y && apt-get install -yq jq && git config --global --add safe.directory /swift-configuration/.git && git config --global --add safe.directory /configuration
+          MATRIX_LINUX_COMMAND: ./Scripts/run-linkage-test.sh
+          MATRIX_LINUX_5_10_ENABLED: false
+          MATRIX_LINUX_6_0_ENABLED: false
+          MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: false
+
+  linkage-test:
+    name: Linkage test
+    needs: construct-linkage-test-matrix
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    with:
+      name: "Integration test"
+      matrix_string: '${{ needs.construct-linkage-test-matrix.outputs.integration-test-matrix }}'

.github/workflows/pull_request.yml

@@ -61,3 +61,30 @@ jobs:
       windows_6_1_enabled: false
       windows_nightly_next_enabled: false
       windows_nightly_main_enabled: false
+
+  construct-linkage-test-matrix:
+    name: Construct linkage matrix
+    runs-on: ubuntu-latest
+    outputs:
+      integration-test-matrix: '${{ steps.generate-matrix.outputs.integration-test-matrix }}'
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+      - id: generate-matrix
+        run: echo "integration-test-matrix=$(curl -s https://raw.githubusercontent.com/apple/swift-nio/main/scripts/generate_matrix.sh | bash)" >> "$GITHUB_OUTPUT"
+        env:
+          MATRIX_LINUX_SETUP_COMMAND: apt-get update -y && apt-get install -yq jq && git config --global --add safe.directory /swift-configuration/.git && git config --global --add safe.directory /configuration
+          MATRIX_LINUX_COMMAND: ./Scripts/run-linkage-test.sh
+          MATRIX_LINUX_5_10_ENABLED: false
+          MATRIX_LINUX_6_0_ENABLED: false
+          MATRIX_LINUX_NIGHTLY_MAIN_ENABLED: false
+
+  linkage-test:
+    name: Linkage test
+    needs: construct-linkage-test-matrix
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    with:
+      name: "Integration test"
+      matrix_string: '${{ needs.construct-linkage-test-matrix.outputs.integration-test-matrix }}'