Suggest an exact alternative in literal_coercion_linter

[MichaelChirico]

is it always possible to suggest an exact alternative? I think it should be. so

as.integer(1) -> suggest 1L
as.numeric(NA) -> suggest NA_real_

etc. looking again I think it's definitely a big enough undertaking to warrant its own PR

Originally posted by @MichaelChirico in #1437 (comment)

[MichaelChirico]

This is done already, AFAICT:

lint(linters = literal_coercion_linter(), "
as.integer(NA)
dbl(NA)
as.numeric(1L)
")

Gives

<text>:2:1: warning: [literal_coercion_linter] Use NA_integer_ instead of as.integer(NA), i.e., use literals directly where possible, instead of coercion.
as.integer(NA)
^~~~~~~~~~~~~~
<text>:3:1: warning: [literal_coercion_linter] Use NA_real_ instead of dbl(NA), i.e., use literals directly where possible, instead of coercion.
dbl(NA)
^~~~~~~
<text>:4:1: warning: [literal_coercion_linter] Use 1 instead of as.numeric(1L), i.e., use literals directly where possible, instead of coercion.
as.numeric(1L)
^~~~~~~~~~~~~~