Release 2.4.2 - C23 errors and minor fixes

What's Changed

• Call i2s_channel_enable(_tx_handle) in AudioOutputSPDIF::begin() by @NeoCat in #799
• Fix u8 upsampling and mono mode for AudioGeneratorWAV by @AlexanderChad in #802
• Fix memory corruption in AudioGeneratorAAC on non-ESP8266 platforms by @wojtekka in #807
• Fix C23 compilation errors by @earlephilhower in #814

New Contributors

• @NeoCat made their first contribution in #799
• @AlexanderChad made their first contribution in #802

Full Changelog: 2.4.1...2.4.2