Sampling error corrected and plotter added

[aguerrerolopez]

Pull Request: Dataloader and Solver Enhancements

Dataloader Resampling Enhancement

• Modification: Updated the dataloader to automatically resample audio inputs to 16kHz if they are not already in that sampling rate.
• Rationale: Previously, the analysis was miscalculated for audios with sampling rates other than 16kHz. This enhancement ensures consistency and accuracy across various input audio formats.

New Hyperparameter in solver.py for Formant Plotting

• Addition: Introduced a new hyperparameter plot_formants in cfg/config.yaml.
• Functionality: When set to true, this parameter enables the plotting of formants. It generates and saves a PNG file for each prediction, using the same name as the .pred file.
• Impact: This feature enhances visualization and analysis of formant tracking, providing a clearer understanding of the model's output.

These modifications aim to improve the usability and functionality of the FormantsTracker tool, making it more versatile and user-friendly.