[libc] Exercise all CMake build types in GitHub Action workflows (#126315)

We want to test libc in all build configurations: Debug, Release and
MinSizeRel which correspond to -O0, -O3 and -Os optimization flags.

Author: petrhosek

.github/workflows/libc-fullbuild-tests.yml

@@ -15,6 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
+        build_type: [Debug, Release, MinSizeRel]
         include:
           - os: ubuntu-24.04
             ccache-variant: sccache
@@ -68,7 +69,7 @@ jobs:
         cmake -B ${{ steps.strings.outputs.build-output-dir }}
         -DCMAKE_CXX_COMPILER=${{ matrix.cpp_compiler }}
         -DCMAKE_C_COMPILER=${{ matrix.c_compiler }}
-        -DCMAKE_BUILD_TYPE=MinSizeRel
+        -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
         -DCMAKE_C_COMPILER_LAUNCHER=${{ matrix.ccache-variant }}
         -DCMAKE_CXX_COMPILER_LAUNCHER=${{ matrix.ccache-variant }}
         -DCMAKE_INSTALL_PREFIX=${{ steps.strings.outputs.build-install-dir }}

.github/workflows/libc-overlay-tests.yml

@@ -16,6 +16,7 @@ jobs:
       # Set fail-fast to false to ensure that feedback is delivered for all matrix combinations.
       fail-fast: false
       matrix:
+        build_type: [Debug, Release, MinSizeRel]
         include:
           # TODO: add linux gcc when it is fixed
           - os: ubuntu-24.04
@@ -95,7 +96,7 @@ jobs:
         cmake -B ${{ steps.strings.outputs.build-output-dir }}
         -DCMAKE_CXX_COMPILER=${{ matrix.compiler.cpp_compiler }}
         -DCMAKE_C_COMPILER=${{ matrix.compiler.c_compiler }}
-        -DCMAKE_BUILD_TYPE=MinSizeRel
+        -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
         -DCMAKE_C_COMPILER_LAUNCHER=${{ matrix.ccache-variant }}
         -DCMAKE_CXX_COMPILER_LAUNCHER=${{ matrix.ccache-variant }}
         -DCMAKE_POLICY_DEFAULT_CMP0141=NEW