CI: Link using -static-libstdc++

This prevents error:

  dibbler-client: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found

(The library exists, but it's GLIBCXX_3.4.20 .)
parent 611fa0c8
Pipeline #876 passed with stage
in 1 minute and 19 seconds