Djm/deprecate

[dajmcdon]

Checklist

Please:

• [x] Make sure this PR is against "dev", not "main".
• [x] Request a review from one of the current epipredict main reviewers: dajmcdon.
• [x] Make sure to bump the version number in DESCRIPTION and NEWS.md. Always increment the patch version number (the third number), unless you are making a release PR from dev to main, in which case increment the minor version number (the second number).
• [x] Describe changes made in NEWS.md, making sure breaking changes (backwards-incompatible changes to the documented interface) are noted. Collect the changes under the next release number (e.g. if you are on 0.7.2, then write your changes under the 0.8 heading).

Change explanations for reviewer

In reviewing #296 , some of the error message changes I was suggesting seemed to borrow from existing tidymodels functions. All of these are internal, and we don't actually need them.

@dsweber2 note also the internal versions of purrr functions. This avoids the need to import the package. These are "in" {rlang} and accessible as usethis::use_standalone("r-lib/rlang", "purrr"), for example.

[dajmcdon]

@dsweber2 OK. I refactored bake.epi_recipe() to fix the issue with the tests I'd removed. This now results (correctly) in an epi_df. But note that the column order is different. It is now the order enforced by epiprocess::as_epi_df.

Also added a test to check that my refactor works as expected.

epi_juice() was internal to bake.epi_recipe() and is no longer needed for anything.

[dajmcdon]

...man/add_model.Rd is getting renamed to man/Add_model.Rd when I run document

Mine as well. I think it's like that on dev.