Fix Memory Management for Printer Objects in CPDB API

[prab0007al]

Description:

This pull request addresses issues related to double freeing and memory leaks in the CPDB library's printer object handling.

Changes Made:

As suggested by @tillkamppeter in issue itself, I have made the following changes:

• Revised Memory Management: The responsibility for freeing printer objects has been moved from the callback function to the cpdbOnPrinterRemoved() function. This ensures that printer objects are freed immediately after the callback is executed.
• Updated Callback Logic: Removed the printer object freeing from the cpdbPrinterCallback() function to prevent double-free errors when custom callbacks are used.

These changes enhance the reliability of the CPDB API and simplify its usage, ensuring developers no longer need to worry about memory management issues.

Fixes Issue #79 cpdbOnPrinterRemoved(): Free printer object directly, do not expect it from the callback