misc: ux/ui rename “swarm” to “group”

A(n) [type] error occurred while {verb} {noun}
createSwarm → createGroup → newGroup
Create swarm → Create new group
startSwarm → startGroup → newGroup
Start swarm → Create new group
swarmName → groupName
Swarm name → Group name

Change-Id: I9cb6f7b124d3db193bd190d2e52b5b27ea10ecf3
GitLab: #1845