Add Python 3.10 support and tests (#9077)

Fixes https://github.com/certbot/certbot/issues/9058.

The changes to the CI config are equivalent to the ones made in https://github.com/certbot/certbot/pull/8460.

Other than ignoring some warnings raised by botocore, the main additional work that had to be done here was switching away from using `distutils.version.LooseVersion` since the entire `distutils` module was deprecated in Python 3.10. To do that, I took a few different approaches:

* If the version strings being parsed are from Python packages such as Certbot or setuptools, I switched to using [pkg_resources.parse_version](https://setuptools.pypa.io/en/latest/pkg_resources.html#parsing-utilities) from `setuptools`. This functionality has been available since [setuptools 8.0 from 2014](https://setuptools.pypa.io/en/latest/history.html#id865).
* If the version strings being parsed are not from Python packages, I added code equivalent to `distutils.version.LooseVersion` in `certbot.util.parse_loose_version`.
* The code for `CERTBOT_PIP_NO_BINARY` can be completely removed since that variable isn't used or referenced anywhere in this repo.

* add python 3.10 support

* make some version changes

* don't use looseversion in setup.py

* switch to pkg_resources

* deprecate get_strict_version

* fix route53 tests

* remove unused CERTBOT_PIP_NO_BINARY code

* stop using distutils in letstest

* add unit tests

* more changelog entries

certbot/tests/util_test.py

@@ -592,6 +592,19 @@ class OsInfoTest(unittest.TestCase):
         self.assertEqual(cbutil.get_python_os_info(), ("testdist", "42"))
 
 
+class GetStrictVersionTest(unittest.TestCase):
+    """Test for certbot.util.get_strict_version."""
+
+    @classmethod
+    def _call(cls, *args, **kwargs):
+        from certbot.util import get_strict_version
+        return get_strict_version(*args, **kwargs)
+
+    def test_it(self):
+        with self.assertWarnsRegex(DeprecationWarning, "get_strict_version"):
+            self._call("1.2.3")
+
+
 class AtexitRegisterTest(unittest.TestCase):
     """Tests for certbot.util.atexit_register."""
     def setUp(self):
@@ -624,5 +637,38 @@ class AtexitRegisterTest(unittest.TestCase):
             atexit_func(*args[1:], **kwargs)
 
 
+class ParseLooseVersionTest(unittest.TestCase):
+    """Test for certbot.util.parse_loose_version.
+
+    These tests are based on the original tests for
+    distutils.version.LooseVersion at
+    https://github.com/python/cpython/blob/v3.10.0/Lib/distutils/tests/test_version.py#L58-L81.
+
+    """
+
+    @classmethod
+    def _call(cls, *args, **kwargs):
+        from certbot.util import parse_loose_version
+        return parse_loose_version(*args, **kwargs)
+
+    def test_less_than(self):
+        comparisons = (('1.5.1', '1.5.2b2'),
+            ('3.4j', '1996.07.12'),
+            ('2g6', '11g'),
+            ('0.960923', '2.2beta29'),
+            ('1.13++', '5.5.kw'))
+        for v1, v2 in comparisons:
+            self.assertLess(self._call(v1), self._call(v2))
+
+    def test_equal(self):
+        self.assertEqual(self._call('8.02'), self._call('8.02'))
+
+    def test_greater_than(self):
+        comparisons = (('161', '3.10a'),
+            ('3.2.pl0', '3.1.1.6'))
+        for v1, v2 in comparisons:
+            self.assertGreater(self._call(v1), self._call(v2))
+
+
 if __name__ == "__main__":
     unittest.main()  # pragma: no cover