[rqd] Fix file logging to handle non-ASCII characters without timestamp

[ramonfigueiredo]

• Updated the logging logic to use the file name for appending logs.
• Corrected file logging to ensure non-ASCII characters are properly handled when RQD_PREPEND_TIMESTAMP is False.
• This change prevents crashes due to TypeError and fixes the broken file logging. self.rqlog is a file object and not a string.

[ramonfigueiredo]

This change fixes the problem found by @lithorus and described in the PR: https://github.com/AcademySoftwareFoundation/OpenCue/pull/1335#discussion_r1679731287