Update GitHub Actions

.github/workflows/main.yml

@@ -9,10 +9,9 @@ jobs:
       run: |
         rm -rf ~/.conda/envs/miplearn-test
         yes | conda create --name miplearn-test python=3.6
-        julia -e 'using Pkg; Pkg.add(PackageSpec(url="https://github.com/iSoron/CPLEXW.git")); Pkg.build("CPLEXW")'
-        julia -e 'using Pkg; Pkg.add(PackageSpec(url="https://github.com/iSoron/TinyBnB.jl.git"))'
+        julia --project=src/julia -e 'using Pkg; Pkg.instantiate()'
         (cd /opt/gurobi900/linux64 && ~/.conda/envs/miplearn-test/bin/python setup.py install)
         (cd /opt/cplex-12.8/cplex/python/3.6/x86-64_linux && ~/.conda/envs/miplearn-test/bin/python setup.py install)
-        ~/.conda/envs/miplearn-test/bin/pip install -r requirements.txt
-        ~/.conda/envs/miplearn-test/bin/pytest
+        ~/.conda/envs/miplearn-test/bin/pip install -r src/python/requirements.txt
+        ~/.conda/envs/miplearn-test/bin/pytest src/python