🚸 add simple timer example with task notify

[Vollbrecht]

A simple example how to notify a task from a hardware timer ISR.
I think using the EspTimer is more useful, but people like to use the Hardware timer directly so that's why i made the example.
CI will tell me if that's is working in newer IDF versions. Might need to rework the API for IDF 5 since they axed the api and now have it called general purpose timer.

[Vollbrecht]

@ivmarkov can you restart the one failed CI job. Looks like a random git issue

[ivmarkov]

Thanks! The new timer driver, a.k.a. the "general purpose timer" we don't support yet, as the legacy timer driver is still supported in ESP IDF 5.X. And honestly, other than the GP C timer relieving you from dealing with specific, MCU-dependent timer peripherals (which we actually want to deal with and model - due to the type safety of our HAL), I don't see other advantages to it - for now.