CONTRIBUTING.md: Update flake8 command (#2124)

* CONTRIBUTING.md: Update flake8 command

* updating DIRECTORY.md

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>

Author: cclauss

CONTRIBUTING.md

@@ -68,11 +68,11 @@ We want your work to be readable by others; therefore, we encourage you to note
   black .
   ```
 
-- All submissions will need to pass the test __flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics__ before they will be accepted so if possible, try this test locally on your Python file(s) before submitting your pull request.
+- All submissions will need to pass the test __flake8 . --ignore=E203,W503 --max-line-length=88__ before they will be accepted so if possible, try this test locally on your Python file(s) before submitting your pull request.
 
   ```bash
   pip3 install flake8  # only required the first time
-  flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
+  flake8 . --ignore=E203,W503  --max-line-length=88 --show-source
   ```
 
 - Original code submission require docstrings or comments to describe your work.

DIRECTORY.md

@@ -395,6 +395,7 @@
   * [Zellers Congruence](https://github.com/TheAlgorithms/Python/blob/master/maths/zellers_congruence.py)
 
 ## Matrix
+  * [Count Islands In Matrix](https://github.com/TheAlgorithms/Python/blob/master/matrix/count_islands_in_matrix.py)
   * [Matrix Class](https://github.com/TheAlgorithms/Python/blob/master/matrix/matrix_class.py)
   * [Matrix Operation](https://github.com/TheAlgorithms/Python/blob/master/matrix/matrix_operation.py)
   * [Nth Fibonacci Using Matrix Exponentiation](https://github.com/TheAlgorithms/Python/blob/master/matrix/nth_fibonacci_using_matrix_exponentiation.py)