adds skip teams flag to byRepos cmd

[amenocal]

This pull request includes updates to the byReposCmd command in the cmd/byRepos.go file to introduce a new flag for skipping teams. The most important changes involve adding the skip-teams flag and ensuring it is properly handled within the command.

This flag is already being leveraged at the create Team api level as an environmental variable to decide whether to skip teams or not.

New flag and environment variable:

• cmd/byRepos.go: Added a new flag skip-teams to the byReposCmd command, which allows users to skip adding members and repos to teams that already exist to save on API requests.
• cmd/byRepos.go: Set the GHMT_SKIP_TEAMS environment variable using the value of the skip-teams flag.
• cmd/byRepos.go: Retrieved the value of the skip-teams flag and assigned it to the skipTeams variable.

[antgrutta]

lgtm