Fix PyLong_FromUnsignedLong on windows, making pip install wheels work

Author: timfel

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/cext/capi/ExternalFunctionNodes.java

@@ -207,7 +207,7 @@ public abstract static class FromLongNode extends CExtToJavaNode {
 
         @Specialization
         static long doInt(int value) {
-            return value;
+            return value & 0xFFFFFFFFL;
         }
 
         @Specialization

graalpython/lib-python/3/venv/__init__.py

@@ -392,9 +392,6 @@ def _setup_pip(self, context):
         # intended for the global Python environment
         cmd = [context.env_exec_cmd, '-Im', 'ensurepip', '--upgrade',
                                                          '--default-pip']
-        # Truffle change for windows bug on graalpy.
-        if sys.platform == 'win32':
-            os.environ['_PIP_STANDALONE_CERT'] = "."
         try:
             subprocess.check_output(cmd, stderr=subprocess.STDOUT)
         except subprocess.CalledProcessError as err: