Fix compiler issue on debian CI build

.gitlab-ci.yml

@@ -8,7 +8,7 @@ debian_10:
   stage: build
   image: "registry.gitlab.com/gerbolyze/build-containers/debian:10"
   script:
-    - "export PATH=$HOME/.local/bin:$HOME/.cargo/bin:$PATH"
+    - "export PATH=$HOME/.local/bin:$HOME/.cargo/bin:$PATH CXX=clang++"
     - "python3 setup.py install --user"
     - "gerbolyze --help"