Combine unit tests with build stage
Combine unit tests with build stage

Pulling docker image wastes time if the testing is in the second stage.

solvcon/solvcon,yungyuc/solvcon,solvcon/solvcon,solvcon/solvcon,yungyuc/solvcon,solvcon/solvcon,yungyuc/solvcon,yungyuc/solvcon,solvcon/solvcon,yungyuc/solvcon,yungyuc/solvcon,solvcon/solvcon