Delete the copy constructor and copy assignment operators for StaticJsonBufferBase.

Created by: luisrayas3

These are always invalid, regardless of usage of objects created in the buffer(s). The root of the problem with using the default copy operators is that the _buffer pointer is copied as well, which means that the copied-to buffer now points to the copied-from buffer's memory.

Consider the clearing example at the bottom of https://arduinojson.org/faq/how-to-reuse-a-jsonbuffer/

StaticJsonBuffer<200> buf{};

JsonObject& obj = buf.createObject();
// Use obj, etc.

buf = StaticJsonBuffer<200>();
// StaticJsonBufferBase::_buffer points to deallocated memory of the temporary

JsonObject& new_obj = buf.createObject();
// Even if I never touch `obj` again, new_obj can easily become corrupted.

Properly implemented copy operators will have to be provided by the concrete buffer types (e.g. StaticJsonBuffer) and something sensible needs to be done about mis-matched capacities.