Update NonBlockingRtttl.cpp

[chechi666]

This version is updated to be compile with the arduino ESP32library V3.3

[end2endzone]

Thank you for this PR. I really appreciate the effort. However, I must preserve backward compatibility with ESP32 core 2.x because I still support other projects which are not updated to ESP32 core 3.x yet.

The changes you've proposed are already covered in the project, so I won't be merging this PR. A similar feature was also added in my other RTTTL library, AnyRtttl and I would like to keep both libraries aligned with each other. EDIT: See these lines for details.

Hope you do not mind that I do not plan on merging your PR even tough you actually tried to contribute to the project. Your input was valuable and as brought attention to this problem that I was ignoring. I hope you will keep contributing if you ever saw other opportunities.

If you would like to be mentionned as a contributor, I can create a new minor release (1.4.1) by integrating your changes in a feature branch. This would list you as an actual contributor to the project. If not, you can close this PR.

Thank you