Add pressure for Brewfather logging option

[tgangso]

Could you please update the log option for Brewfather to include pressure? Thanks.

Full format string: {"id":"FERMENTER1","tempUnit":"C","beerTemp":%b,"beerSet":%B,"fridgeTemp":%f,"fridgeSet":%F,"roomTemp":%r,"gravity":%g,"tiltValue":%t,"auxTemp":%a,"extVolt":%v,"timestamp":%u,"pressure":%P}

ref feature request: https://gitlab.com/warpkode/public/brewfather/-/issues/920