CI: ubuntu 24.04 => use deb package for gcovr, since it's nearly the latest stable version now

Author: Totto16

.github/workflows/test.yml

@@ -33,8 +33,7 @@ jobs:
         run: |
           sudo apt-get update
           sudo apt-get upgrade -y
-          sudo apt-get install ninja-build libsdl2-2.0-0 libsdl2-dev libsdl2-ttf* libsdl2-mixer* libsdl2-image* -y
-          pip install gcovr
+          sudo apt-get install ninja-build libsdl2-2.0-0 libsdl2-dev libsdl2-ttf* libsdl2-mixer* libsdl2-image* gcovr -y
 
       - name: Configure
         run: meson setup build -Dbuildtype=debug -Db_coverage=true -Dtests=true  -Dclang_libcpp=enabled