remove extra quote from workflow

Author: cdueben

.github/workflows/R-CMD-check.yaml

@@ -48,7 +48,7 @@ jobs:
         run: |
           echo "CC=/usr/local/opt/llvm@16/bin/clang -mmacos-version-min=13" >> $GITHUB_ENV
           echo "CXX=/usr/local/opt/llvm@16/bin/clang++ -mmacos-version-min=13" >> $GITHUB_ENV
-          echo "LDFLAGS="-L/opt/homebrew/opt/llvm@16/lib/c++ -Wl,-rpath,/opt/homebrew/opt/llvm@16/lib/c++" >> $GITHUB_ENV
+          echo "LDFLAGS=-L/opt/homebrew/opt/llvm@16/lib/c++ -Wl,-rpath,/opt/homebrew/opt/llvm@16/lib/c++" >> $GITHUB_ENV
           echo "CPPFLAGS=-I/usr/local/opt/llvm@16/include" >> $GITHUB_ENV
           echo 'export PATH="/opt/homebrew/opt/llvm@16/bin:$PATH"' >> /Users/runner/.bash_profile