Allow running tests when static library is disabled

We then only run a subset of the tests, but still better than failing to
build.

Signed-off-by: Steffen Jaeckel <jaeckel-floss@eyet-services.de>

.github/workflows/main.yml

@@ -24,6 +24,7 @@ jobs:
            - { configure: '--disable-tls'       }
            - { configure: '--enable-cares'      }
            - { configure: '--disable-getrandom' }
+           - { configure: '--disable-static'    }
     name: Regular Tests
     steps:
       - uses: actions/checkout@v2