Fix more test failures

Author: slozier

tests/IronPython.Tests/Cases/IronPythonCasesManifest.ini

@@ -206,3 +206,6 @@ RunCondition=$(IS_POSIX) # Module resource is Posix-specific
 [IronPython.modules.system_related.test_sys_getframe]
 IsolationLevel=PROCESS # https://github.com/IronLanguages/ironpython3/issues/489
 FullFrames=true
+
+[IronPython.modules.system_related.test_sys]
+RunCondition=NOT $(IS_NETCOREAPP) # https://github.com/IronLanguages/ironpython3/issues/2055

tests/suite/test_array_stdlib.py

@@ -8,7 +8,7 @@
 
 import sys
 
-from iptest import is_ironpython, generate_suite, run_test
+from iptest import is_ironpython, generate_suite, run_test, is_posix
 
 import test.test_array
 
@@ -64,6 +64,10 @@ def load_tests(loader, standard_tests, pattern):
                 test.test_array.UnsignedShortTest('test_subclass_with_kwargs'), # https://github.com/IronLanguages/ironpython3/issues/767
                 test.test_array.UnsignedShortTest('test_type_error'), # https://github.com/IronLanguages/ironpython3/issues/767
             ]
+            if is_posix:
+                failing_tests += [
+                    test.test_array.LongTest('test_overflow'), # https://github.com/IronLanguages/ironpython3/issues/767
+                ]
 
         skip_tests = []