ci: update build workflow to use llvm 20 on macos

Author: Totto16

.github/workflows/build.yml

@@ -182,10 +182,10 @@ jobs:
         if: matrix.config.os == 'macos'
         run: |
           brew update
-          brew install llvm@19 lld@19
-          echo "$(brew --prefix)/opt/llvm@19/bin:$(brew --prefix)/opt/lld@19/bin" >> $GITHUB_PATH
-          echo "LDFLAGS=-L$(brew --prefix)/opt/llvm@19/lib -L$(brew --prefix)/opt/llvm@19/lib/c++ -Wl,-rpath,$(brew --prefix)/opt/llvm@19/lib/c++ -L$(brew --prefix)/opt/lld@19/lib" >> "$GITHUB_ENV"
-          echo "CPPFLAGS=-I$(brew --prefix)/opt/llvm@19/include -I$(brew --prefix)/opt/lld@19/include" >> "$GITHUB_ENV"
+          brew install llvm@20 lld@20
+          echo "$(brew --prefix)/opt/llvm@20/bin:$(brew --prefix)/opt/lld@20/bin" >> $GITHUB_PATH
+          echo "LDFLAGS=-L$(brew --prefix)/opt/llvm@20/lib -L$(brew --prefix)/opt/llvm@20/lib/c++ -Wl,-rpath,$(brew --prefix)/opt/llvm@20/lib/c++ -L$(brew --prefix)/opt/lld@20/lib" >> "$GITHUB_ENV"
+          echo "CPPFLAGS=-I$(brew --prefix)/opt/llvm@20/include -I$(brew --prefix)/opt/lld@20/include" >> "$GITHUB_ENV"
           echo "CC=clang" >> "$GITHUB_ENV"
           echo "CXX=clang++" >> "$GITHUB_ENV"
           echo "OBJC=clang" >> "$GITHUB_ENV"