set the compiler to gcc-13 (fix typo)

Author: andersc

.github/workflows/ubuntu-22-04-build.yml

@@ -20,7 +20,7 @@ jobs:
           sudo apt-get install -y gcc-13 build-essential
       - name: CMake set-up
         run: |
-          export CXX=/usr/bin/g++-13ß
+          export CXX=/usr/bin/g++-13
           cmake -DHMDF_TESTING=ON -DHMDF_EXAMPLES=ON -DHMDF_BENCHMARKS=ON -DCMAKE_BUILD_TYPE=Release .
       - name: CMake build
         run: cmake --build . --config Release --parallel $(nproc)