[MM-56073] MMCTL delete post command (#27539)

Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>

server/cmd/mmctl/client/client.go

@@ -159,4 +159,6 @@ type Client interface {
 	GetPreferenceByCategoryAndName(ctx context.Context, userId, category, preferenceName string) (*model.Preference, *model.Response, error)
 	UpdatePreferences(ctx context.Context, userId string, preferences model.Preferences) (*model.Response, error)
 	DeletePreferences(ctx context.Context, userId string, preferences model.Preferences) (*model.Response, error)
+	PermanentDeletePost(ctx context.Context, postID string) (*model.Response, error)
+	DeletePost(ctx context.Context, postId string) (*model.Response, error)
 }