fix(tests): restore explicit Windows check for fork context

Author: sterchelen

opentelemetry-sdk/tests/metrics/test_meter_provider_fork.py

@@ -17,11 +17,12 @@
 import multiprocessing
 import os
 import unittest
+from platform import system
 
 from opentelemetry.sdk.metrics import MeterProvider
 from opentelemetry.sdk.resources import Resource
 
-_fork_ctx = multiprocessing.get_context("fork") if hasattr(os, "fork") else None
+_fork_ctx = multiprocessing.get_context("fork") if system() != "Windows" else None
 
 
 @unittest.skipUnless(

opentelemetry-sdk/tests/trace/test_tracer_provider_fork.py

@@ -17,11 +17,12 @@
 import multiprocessing
 import os
 import unittest
+from platform import system
 
 from opentelemetry.sdk.resources import Resource
 from opentelemetry.sdk.trace import TracerProvider
 
-_fork_ctx = multiprocessing.get_context("fork") if hasattr(os, "fork") else None
+_fork_ctx = multiprocessing.get_context("fork") if system() != "Windows" else None
 
 
 @unittest.skipUnless(