simplify github workflows

.github/workflows/macos_install.yml

@@ -22,7 +22,7 @@ concurrency:
 
 jobs:
   macos-build:
-    runs-on: macos-latest
+    runs-on: macos-15
     strategy:
       matrix:
         include:

.github/workflows/ubuntu.yml

@@ -22,11 +22,12 @@ concurrency:
 
 jobs:
   ubuntu-build:
-    runs-on: ubuntu-22.04
     strategy:
       matrix:
         shared: [ON, OFF]
         cxx: [g++-12, clang++-14]
+        runs-on: [ubuntu-22.04, ubuntu-22.04-arm]
+    runs-on: ${{matrix.runs-on}}
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
       - name: Setup Ninja

.github/workflows/ubuntu_install.yml

@@ -25,15 +25,16 @@ jobs:
     runs-on: ubuntu-24.04
     strategy:
       matrix:
-        include:
-          shared: [ON, OFF]
-          cxx: [g++-12, clang++]
+        shared: [ON, OFF]
+        cxx: [g++-12, clang++]
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
       - name: Setup Ninja
         run: sudo apt-get install ninja-build
       - name: Prepare
         run: cmake -D ADA_TESTING=ON -G Ninja -DBUILD_SHARED_LIBS=${{matrix.shared}} -DCMAKE_INSTALL_PREFIX:PATH=destination -B build
+        env:
+          CXX: ${{matrix.cxx}}
       - name: Build
         run: cmake --build build -j=4
       - name: Install

.github/workflows/visual_studio.yml

@@ -23,7 +23,7 @@ concurrency:
 jobs:
   ci:
     name: windows-vs17
-    runs-on: windows-latest
+    runs-on: windows-2025
     strategy:
       fail-fast: false
       matrix:

.github/workflows/visual_studio_clang.yml

@@ -23,7 +23,7 @@ concurrency:
 jobs:
   ci:
     name: windows-vs17
-    runs-on: windows-latest
+    runs-on: windows-2025
     strategy:
       fail-fast: false
       matrix: