Only show first class in {.obj_type_friendly}

[olivroy]

To display like rlang
r-lib/rlang#1622

Let me know if you think this is reasonable, and if it requires NEWS.

cli::cli_abort("{.obj_type_friendly {gt::gt(gt::exibble)}}")
Error:
! a <gt_tbl/list> object

With this PR (hopefully)

cli::cli_abort("{.obj_type_friendly {gt::gt(gt::exibble)}}")
Error:
! a <gt_tbl> object

[gaborcsardi]

Thanks!