Your goal for this challenge is to write a Python function to build a ZIP archive.
you want to include, a list of file extensions, and an output file path for the resulting archive.
The function should search the input directory and all of its subdirectories for files with the specified extension and then package them together into a ZIP file.
Zip file should maintain folder structure relative to the top-level directory.
for e.g.
zip_all(r'.\my_stuff', ['.png'], 'my_stuff.zip')