ci: run macOS and iOS tests also on macOS 14

The macOS 14 runners are ARM64 (in the non "large" version) whereas
macOS 13 runners are still x64, so keep that one around too.

.github/workflows/CI-unix.yml

@@ -77,7 +77,11 @@ jobs:
           adb shell "cd /data/local/tmp/build ; env UV_TEST_TIMEOUT_MULTIPLIER=5 ./uv_run_tests_a"
 
   build-macos:
-    runs-on: macos-12
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-13, macos-14]
     steps:
       - uses: actions/checkout@v4
       - name: Envinfo
@@ -112,7 +116,11 @@ jobs:
           make -C build-auto -j4
 
   build-ios:
-    runs-on: macos-12
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-13, macos-14]
     steps:
       - uses: actions/checkout@v4
       - name: Configure

.github/workflows/sanitizer.yml

@@ -67,7 +67,7 @@ jobs:
           ./build-ubsan/uv_run_tests_a
 
   sanitizers-macos:
-    runs-on: macos-12
+    runs-on: macos-13
     steps:
       - uses: actions/checkout@v4