Race condition in ProcessChecker.remove_lock_file()

[kozlovsky]

When starting Tribler core, FileNotFoundError happened in ProcessChecker.remove_lock_file:

FileNotFoundError: [WinError 2]: 'C:\\Users\\<user>\\AppData\\Roaming\\.Tribler\\triblerd.lock'
  File "run_tribler.py", line 69, in <module>
  File "tribler_core\start_core.py", line 135, in start_tribler_core
  File "tribler_common\process_checker.py", line 26, in __init__
  File "tribler_common\process_checker.py", line 61, in remove_lock_file
  File "pathlib.py", line 1321, in unlink

It seems the previous core process was finishing execution and removed lock file right after lock_file_path.exists() checked that the file is present:

    def remove_lock_file(self):
        """
        Remove the lock file if it exists.
        """
        if self.lock_file_path.exists():
            self.lock_file_path.unlink()  # <- here 

The missing_ok=True option can be added to the unlink call to prevent it.

[sentry-for-tribler]

Sentry issue: TRIBLER-D0