New block suggestion: update and upgrade OS packages

[dkirkby]

This can already be achieved using a pair of "Run Command" blocks, but it might be worth creating a dedicated block to encourage best practices and save people the trouble of looking up the relevant commands and modifying them to run non-interactively:

sudo DEBIAN_FRONTEND=noninteractive apt-get -y update
sudo DEBIAN_FRONTEND=noninteractive apt-get -y dist-upgrade

[AntoCuc]

Further to the above it would allow users to further abstract the Raspbian-specific commands. In the event in which pibakery, in the future, may support more than on RPi OS.

[davidferguson]

This has now ben committed to the repo, and will be pushed out to users in the next PiBakery block update.