ADDED: rwlocks unit tests for safety and reliability

[younes-io]

I added new tests for the rwlocks module:

• A test to check if priority handling works correctly
• A test to make sure timeouts work as expected
• A test to check if write operations block read operations
• A test to see if multiple read operations can happen at the same time
• A test to check what happens with invalid modes

I also added some code to clean up after the tests run.

Please let me know your thoughts. This is my first contribution to this repo!