Use a modern (brew) LLVM version

The macOS ones is so old, it can't even handle `--version`! :(

Author: pcolby

.github/workflows/build.yaml

@@ -218,9 +218,8 @@ jobs:
       #- run: find / -name 'llvm-profdata*'
       #- run: find / -name 'llvm-cov*'
       - run: |
-          /Library/Developer/CommandLineTools/usr/bin/llvm-profdata --version
-          /Library/Developer/CommandLineTools/usr/bin/llvm-cov --version
-          /Library/Developer/CommandLineTools/usr/bin/llvm-cov export --help
+          /opt/homebrew/Cellar/llvm@18/18.1.8/bin/llvm-profdata --version
+          /opt/homebrew/Cellar/llvm@18/18.1.8/bin/llvm-cov --version
       - name: Install lcov
         run: brew install lcov
       - name: Install Qt
@@ -265,8 +264,8 @@ jobs:
           cmake -D CMAKE_BUILD_TYPE=Release \
                 -D CODECOV_GCOV=${{ startsWith(matrix.env.cc, 'gcc') && '/usr/local/bin/gcov-14' || '/usr/bin/gcov'}} \
                 -D ENABLE_COVERAGE=${{ matrix.env.coverage }} \
-                -D LLVM_COV=/Library/Developer/CommandLineTools/usr/bin/llvm-cov \
-                -D LLVM_PROFDATA=/Library/Developer/CommandLineTools/usr/bin/llvm-profdata \
+                -D LLVM_COV=/opt/homebrew/Cellar/llvm@18/18.1.8/bin/llvm-cov \
+                -D LLVM_PROFDATA=/opt/homebrew/Cellar/llvm@18/18.1.8/bin/llvm-profdata \
                 -D QT_INSTALL_DOCS="$RUNNER_WORKSPACE/Qt/Docs/Qt-${{ matrix.qt }}" \
                 -S "$GITHUB_WORKSPACE" -B "$RUNNER_TEMP"
           echo "dokitVersion=$(cat "$RUNNER_TEMP/version.txt")" | tee -a "$GITHUB_OUTPUT"