Revert "GitHub CI: drop libbenchmark1"

This reverts commit d7bbb80.

.github/workflows/cmake.yml

@@ -55,7 +55,7 @@ jobs:
     - name: Install gtest manually
       run: |
         sudo apt-get install libgtest-dev && cd /usr/src/gtest && sudo cmake CMakeLists.txt && sudo make && sudo cp lib/*.a /usr/lib && sudo ln -s /usr/lib/libgtest.a /usr/local/lib/libgtest.a && sudo ln -s /usr/lib/libgtest_main.a /usr/local/lib/libgtest_main.a
-        sudo apt install libbenchmark-dev
+        sudo apt install libbenchmark1 libbenchmark-dev
 
     - name: Create Build Environment
       run: cmake -E make_directory ${{github.workspace}}/mdspan-build