Add Connections pane integration for `tbl_connect` tibbles

[colearendt]

This example from the README should get you what you need:

library(connectapi)
client <- connect()

users <- tbl_connect(client, "users")
groups <- tbl_connect(client, "groups")
shiny_usage <- tbl_connect(client, "shiny_usage")
content_visits <- tbl_connect(client, "content_visits")
all_content <- tbl_connect(client, "content")

all_shiny_usage <- shiny_usage %>% dplyr::collect()

Specifically, all options are tracked here: https://github.com/rstudio/connectapi/blob/6aa577379c8b7b2f782113f2644317ab5b91256d/R/lazy.R#L25

If it would be helpful to put that in a variable or something somewhere, we can totally do that. Note the "schema" is stored too:

https://github.com/rstudio/connectapi/blob/6aa577379c8b7b2f782113f2644317ab5b91256d/R/lazy.R#L38