Restrict pyparsing version to 2.x.x.

The autowrap code is not compatible with pyparsing 3.x.x. Fixes #210.

PiperOrigin-RevId: 405526958
Change-Id: I909c1c5205fbe31edac97d14a33fb1950cc1d6a5

setup.py

@@ -175,7 +175,7 @@ def is_excluded(s):
 
 setup(
     name='dm_control',
-    version='0.0.403778684',
+    version='0.0.405526958',
     description='Continuous control environments and MuJoCo Python bindings.',
     author='DeepMind',
     license='Apache License, Version 2.0',
@@ -193,7 +193,7 @@ def is_excluded(s):
         'numpy >= 1.9.0',
         'protobuf >= 3.15.6',
         'pyopengl >= 3.1.4',
-        'pyparsing',
+        'pyparsing < 3.0.0',
         'requests',
         'setuptools!=50.0.0',  # https://github.com/pypa/setuptools/issues/2350
         'scipy',