tests/micropython: Add test for int.from_bytes with many zero bytes.

tests/micropython/heapalloc_int_from_bytes.py

@@ -5,4 +5,5 @@ import micropython
 micropython.heap_lock()
 print(int.from_bytes(b"1", "little"))
 print(int.from_bytes(b"12", "little"))
+print(int.from_bytes(b"2\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", "little"))
 micropython.heap_unlock()

tests/micropython/heapalloc_int_from_bytes.py.exp

 49
 12849
+50