docs: shorten help and migration texts to gh-like brevity

Long texts no longer restate the flag list, the instance selection
of tea help environment, the config keys with descriptions or the
team argument rules shown under ARGUMENTS; webhook events come from
services.WebhookEvents; the migration guide refers to tea help
formatting for the terminal layout.

Signed-off-by: bircni <bircni@icloud.com>

internal/app/teams.go

@@ -91,9 +91,7 @@ func (a *application) completeTeamThen(next func(ctx context.Context, t target,
 
 func (a *application) teamCommand() *cobra.Command {
 	group := &cobra.Command{Use: "team", Short: "Manage organization teams and access", Long: `Manage the teams of an organization: what they may do in its repositories, who belongs to
-them, and which repositories they can reach.
-
-` + teamArguments}
+them, and which repositories they can reach.`}
 	group.AddCommand(a.teamListCommand(), a.teamViewCommand(), a.teamCreateCommand(), a.teamEditCommand(), a.teamDeleteCommand(), a.teamMemberCommand(), a.teamRepoCommand())
 	return group
 }
@@ -485,9 +483,7 @@ func joinNames(names []string) string {
 
 func (a *application) teamMemberCommand() *cobra.Command {
 	group := &cobra.Command{Use: "member", Short: "Manage team members", Long: `List, add and remove the members of a team. Adding a user to a team of an organization
-also makes them a member of the organization.
-
-` + teamArguments}
+also makes them a member of the organization.`}
 	var limit, page int
 	list := &cobra.Command{
 		Use: "list <team>", Short: "List team members", Args: argsExact(1), ValidArgsFunction: a.completeTeams(),
@@ -585,9 +581,7 @@ func teamRepository(team services.Team, raw string) (string, error) {
 
 func (a *application) teamRepoCommand() *cobra.Command {
 	group := &cobra.Command{Use: "repo", Short: "Manage team repository access", Long: `List the repositories a team can reach, and grant or revoke its access to repositories of
-its organization. Repositories are named alone, such as service, or as ORG/NAME.
-
-` + teamArguments}
+its organization. Repositories are named alone, such as service, or as ORG/NAME.`}
 	var limit, page int
 	list := &cobra.Command{
 		Use: "list <team>", Short: "List team repositories", Args: argsExact(1), ValidArgsFunction: a.completeTeams(),