OpenFermion tutorial moved to recirq, delete it (quantumlib#5453)

Per quantumlib/OpenFermion#783, this tutorial has been moved into the OpenFermion docs. Delete it as well as references to it. 

Only merge with cl/453260770

dev_tools/notebooks/isolated_notebook_test.py

@@ -75,8 +75,6 @@
     "examples/*fidelity*",
     # Also skipping stabilizer code testing.
     "examples/*stabilizer_code*",
-    # Until openfermion is upgraded, this version of Cirq throws an error
-    "docs/tutorials/educators/chemistry.ipynb",
     *NOTEBOOKS_DEPENDING_ON_UNRELEASED_FEATURES,
 ]
 
@@ -181,7 +179,7 @@ def test_notebooks_against_released_cirq(partition, notebook_path, cloned_env):
 mkdir -p out/{notebook_rel_dir}
 cd {notebook_env}
 . ./bin/activate
-pip list 
+pip list
 papermill {rewritten_notebook_path} {os.getcwd()}/{out_path}"""
     stdout, stderr, status = shell_tools.run_shell(
         cmd=cmd,

dev_tools/notebooks/notebook_test.py

@@ -37,9 +37,6 @@
     # skipping fidelity estimation due to
     # https://github.com/quantumlib/Cirq/issues/3502
     "examples/*fidelity*",
-    # chemistry.ipynb requires openfermion, that installs cirq 0.9.1, which interferes
-    # with testing cirq itself...
-    'docs/tutorials/educators/chemistry.ipynb',
     'docs/noise.ipynb',
 ]