Delete copy ctor, assignment operator also in !defined(WITH_THREAD) section.

Author: rwgk

include/pybind11/gil.h

@@ -40,10 +40,14 @@ class gil_scoped_release {
 #else
 
 class gil_scoped_acquire {
+    gil_scoped_acquire(const gil_scoped_acquire &) = delete;
+    gil_scoped_acquire &operator=(const gil_scoped_acquire &) = delete;
     void disarm() {}
 };
 
 class gil_scoped_release {
+    gil_scoped_release(const gil_scoped_release &) = delete;
+    gil_scoped_release &operator=(const gil_scoped_acquire &) = delete;
     void disarm() {}
 };