Delete widget cause crash if widget is an image

## Version of Dear PyGui

Version: 0.6.157
Operating System: Ubuntu 18.04 (Windows 10, macOs xx, Ubuntu 20.04, etc.)

## My Issue/Question

Delete widget cause crash ( Segmentation fault (core dumped) ) if widget contains an image ( or image button). Otherwise it works fine.

## To Reproduce
I follow the example in https://github.com/hoffstadt/DearPyGui/wiki/Runtime-Adding-and-Deleting-Widgets .
# Example code
```python
from dearpygui.core import *
from dearpygui.simple import *

def add_widgets(sender, data):

with window("Secondary Window"): # simple
#add_button("New Button")
add_image_button("image","/home/quannm/DearPyGui/GUI/0183_c6s1_042351_01.jpg",show=True)
def delete_children(sender, data):
delete_item("Secondary Window", children_only=True)

show_debug()

with window("Tutorial"):
add_button("Add Window and Items", callback=add_widgets)
add_button("Delete Window's Children", callback=delete_children)
start_dearpygui()
```
## Expected behavior

If you add button , the code works as intended. However, if you add an image ( or image button), the program crash when you try to delete widget.