Drop Debian 10 support

We need to do a major release anyways and Debian 10 is already out of
regular support.

Author: bastelfreak

metadata.json

@@ -47,7 +47,6 @@
     {
       "operatingsystem": "Debian",
       "operatingsystemrelease": [
-        "10",
         "11",
         "12"
       ]