`ipywidgets.Output` always add newline to `print`, even when asked not to.

[lgautier]

Description

The Python function print() accepts a parameter end to specify what to add at the end of the print. The default is the new line character but this can be changed.

Reproduce

import ipywidgets
output = ipywidgets.Output()
display(output)

for i in range(10):
  with output:
    print(i, end=', ', flush=True)

Expected behavior

Printing on the same line as achieved when Output is not involved:

for i in range(10):
  print(i, end=', ', flush=True)

Context

• ipywidgets version 7.7.1
• Operating System and version: Colab
• Browser and version: Firefox