Make PySimpleQueueType static. (GH-8175)

(cherry picked from commit 9b50a7f29b761920c04d8c3435d216145da15311)

Co-authored-by: Benjamin Peterson <benjamin@python.org>
diff --git a/Modules/_queuemodule.c b/Modules/_queuemodule.c
index 8715337..0eb9930 100644
--- a/Modules/_queuemodule.c
+++ b/Modules/_queuemodule.c
@@ -8,7 +8,7 @@
 [clinic start generated code]*/
 /*[clinic end generated code: output=da39a3ee5e6b4b0d input=cf49af81bcbbbea6]*/
 
-extern PyTypeObject PySimpleQueueType;  /* forward decl */
+static PyTypeObject PySimpleQueueType;  /* forward decl */
 
 static PyObject *EmptyError;
 
@@ -306,7 +306,7 @@
 };
 
 
-PyTypeObject PySimpleQueueType = {
+static PyTypeObject PySimpleQueueType = {
     PyVarObject_HEAD_INIT(NULL, 0)
     "_queue.SimpleQueue",               /*tp_name*/
     sizeof(simplequeueobject),          /*tp_size*/