Describe your change:

Upon executing physics/n_body_simulation.py the error occured:

Traceback (most recent call last):
  File "/home/simon/Documents/pythonProjects/educational/TheAlgorithms-Python/physics/n_body_simulation.py", line 341, in <module>
    plot("Figure-8 solution to the 3-body-problem", example_1(), -2, 2, -2, 2)
  File "/home/simon/Documents/pythonProjects/educational/TheAlgorithms-Python/physics/n_body_simulation.py", line 229, in plot
    fig.canvas.set_window_title(title)
AttributeError: 'FigureCanvasQTAgg' object has no attribute 'set_window_title'

The set_window_title method has been deprecated in Matplotlib 3.4. Apparently, a quick fix is to use fig.canvas.manager.set_window_title instead.

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• Documentation change?

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• All new Python files are placed inside an existing directory.
• All filenames are in all lowercase characters with no spaces or dashes.
• All functions and variable names follow Python naming conventions.
• All function parameters and return values are annotated with Python type hints.
• All functions have doctests that pass the automated testing.
• All new algorithms include at least one URL that points to Wikipedia or another similar explanation.
• If this pull request resolves one or more open issues then the description above includes the issue number(s) with a closing keyword: "Fixes #ISSUE-NUMBER".