Rethink "Add test to store" Prompt

[brodieG]

For example, not sure it should come up in this instance where we just put an arbitrary expression at the prompt:

> validate(INT.1 || NULL || LGL, "hello", format = "full")
Error in validate(INT.1 || NULL || LGL, "hello", format = "full") : 
  For argument `current` at least one of these should pass:
  - `"hello"` should be type "integer-like" (is "character")
  - `"hello"` should be "NULL" (is "character")
  - `"hello"` should be type "logical" (is "character")

unitizer> validate(INT.1 || NULL || LGL, "hello")
Error in validate(INT.1 || NULL || LGL, "hello") : 
  At least one of these should pass:
  - `"hello"` should be type "integer-like" (is "character")
  - `"hello"` should be "NULL" (is "character")
  - `"hello"` should be type "logical" (is "character")

| Add test to store ([Y]es, [N]o, [P]rev, [B]rowse, [R]erun, [Q]uit, [H]elp)?

unitizer> 

Note that the second expression is something we entered as opposed to unitizer showing it on its own.