Added MAiNGO appsi-interface

.github/workflows/test_branches.yml

@@ -268,6 +268,8 @@ jobs:
                 || echo "WARNING: Gurobi is not available"
             python -m pip install --cache-dir cache/pip xpress \
                 || echo "WARNING: Xpress Community Edition is not available"
+            python -m pip install --cache-dir cache/pip maingopy \
+                || echo "WARNING: MAiNGO is not available"
             if [[ ${{matrix.python}} == pypy* ]]; then
                 echo "skipping wntr for pypy"
             else

.github/workflows/test_pr_and_main.yml

@@ -298,6 +298,8 @@ jobs:
                 || echo "WARNING: Gurobi is not available"
             python -m pip install --cache-dir cache/pip xpress \
                 || echo "WARNING: Xpress Community Edition is not available"
+            python -m pip install --cache-dir cache/pip maingopy \
+                || echo "WARNING: MAiNGO is not available"
             if [[ ${{matrix.python}} == pypy* ]]; then
                 echo "skipping wntr for pypy"
             else

pyomo/contrib/appsi/solvers/__init__.py

@@ -15,3 +15,4 @@
 from .cplex import Cplex
 from .highs import Highs
 from .wntr import Wntr, WntrResults
+from .maingo import MAiNGO, MAiNGOTest