remove size limit on displayio.Group

[dhalbert]

Group full messages can be confusing. Could we make Group not need a size limit? It could be like a list, or it could resize itself as necessary.

See for example adafruit/Adafruit_CircuitPython_Display_Text#11

[dastels]

Would this lead to accidentally adding groups (which is what the limit guards against) and getting an even more confusing out of memory error?

[jepler]

make group.size a settable property, possibly increase-only? that would prevent "accidental" addition of groups, since you have to explicitly ask for the increase. it would address the label use-case for not requiring the size to be specified upfront.

[kmatch98]

Closed by: #4233