remove dependency on pytato

- add pytato to requirements.txt of downstream projects to make them
  compatible with PytatoArrayContext

.github/workflows/ci.yml

@@ -119,6 +119,8 @@ jobs:
 
                 sed -i "/egg=arraycontext/ c git+file://$(readlink -f ..)#egg=arraycontext" requirements.txt
 
+                echo "git+https://github.com/inducer/pytato.git#egg=pytato" >> requirements.txt
+
                 # Avoid slow or complicated tests in downstream projects
                 export PYTEST_ADDOPTS="-k 'not (slowtest or octave or mpi)'"
 

setup.py

@@ -44,7 +44,6 @@ def main():
             "loopy>=2019.1",
             "dataclasses; python_version<'3.7'",
             "types-dataclasses",
-            "pytato"
         ],
         package_data={"arraycontext": ["py.typed"]},
     )