Add GitHub workflow to build Clang tool based header generator

Drive-by:
- Add flags to link libgcc and libstdc++ statically into the binary, making it
  "mostly static"
PiperOrigin-RevId: 532349354
Change-Id: I0a86eb29b6a40aec4cec3cffeaf9511726ee4dc8

.github/workflows/debian-sapi-generator-tool.yml

@@ -0,0 +1,59 @@
+name: sapi-generator-tool
+on: push
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    container: debian:10.13
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Cache dependencies
+      uses: actions/cache@v3
+      with:
+        key: debian-10.13-clang16
+        path: |
+          ${{github.workspace}}/build/_deps
+
+    - name: Install build tools
+      run: |
+        apt-get update
+        env DEBIAN_FRONTEND=noninteractive \
+          apt-get install -qy --no-install-recommends \
+            build-essential \
+            ca-certificates \
+            cmake \
+            file \
+            git \
+            gnupg \
+            libc6-dev \
+            lsb-release \
+            make \
+            software-properties-common \
+            wget
+        wget https://apt.llvm.org/llvm.sh
+        chmod +x llvm.sh
+        ./llvm.sh 16 all
+
+    - name: Install ninja-build tool
+      uses: seanmiddleditch/gha-setup-ninja@v3
+
+    - name: Create Build Environment
+      run: |
+        cmake -E make_directory $GITHUB_WORKSPACE/build
+
+    - name: Configure CMake
+      run: |
+        cmake \
+          -S $GITHUB_WORKSPACE \
+          -B $GITHUB_WORKSPACE/build \
+          -G Ninja \
+          -DCMAKE_BUILD_TYPE=Release \
+          -DSAPI_ENABLE_CLANG_TOOL=ON \
+          -DSAPI_ENABLE_CLANG_TOOL_STATIC=ON
+
+    - name: Build
+      run: |
+        cmake \
+          --build $GITHUB_WORKSPACE/build \
+          --config Release \
+          --target sapi_generator_tool

sandboxed_api/tools/clang_generator/CMakeLists.txt

@@ -128,6 +128,13 @@ target_link_libraries(sapi_generator_tool PRIVATE
   sapi::fileops
   sapi::generator
 )
+if(SAPI_ENABLE_CLANG_TOOL_STATIC)
+  target_link_options(sapi_generator_tool PRIVATE
+    # These work for both GCC and Clang
+    -static-libgcc
+    -static-libstdc++
+  )
+endif()
 
 if(BUILD_TESTING AND SAPI_BUILD_TESTING)
   add_executable(sapi_generator_test