Disable python 3.8 incompatible doctest (#2831)

src/conftest.py

@@ -41,6 +41,27 @@ def pytest_runtest_makereport(item, call):
     return tr
 
 
+# These tests require python packages that are no longer built for python 3.8
+PYTHON_38_SKIPS = {
+    "snowpark.session.Session.replicate_local_environment",
+    "snowpark.session.Session.table_function",
+}
+
+DocTestFinder = doctest.DocTestFinder
+
+
+class CustomDocTestFinder(DocTestFinder):
+    def _find(self, tests, obj, name, module, source_lines, globs, seen):
+        if name in PYTHON_38_SKIPS and sys.version_info < (3, 9):
+            return
+        return DocTestFinder._find(
+            self, tests, obj, name, module, source_lines, globs, seen
+        )
+
+
+doctest.DocTestFinder = CustomDocTestFinder
+
+
 # scope is module so that we ensure we delete the session before
 # moving onto running the tests in the tests dir. Having only one
 # session is important to certain UDF tests to pass , since they