docs: Adds details to attend issues #295, #287, #221, #199

[JavierMtzRdz]

Checklist

Please:

• Make sure this PR is against "dev", not "main" (unless this is a release
  PR).
• Request a review from one of the current epidatr main reviewers:
  brookslogan, dshemetov, nmdefries, dsweber2.
• Makes sure to bump the version number in DESCRIPTION. 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).
• 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
  1.7.2, then write your changes under the 1.8 heading).

Change explanations for reviewer

• Issue docs: auth keys instructions #295: Description for save_api_key is inaccurate.

• Change: Provide a clearer explanation as in the message linked to the function.

• Issue Small function documentation details updates #287: The pvt_meta_norostat locations parameter lacks valid inputs.

• Change: Provides a clearer explanation.

• Issue Reduce doc duplication in general and for version-related params #221: Reduce duplication

• Change: Adds a .epidatr_shared_params list of parameters that includes shared parameters and inherits shared parameters in the specific functions' documentation.

• Issue document versions, issues, as_of, and recommendations #199: Group as_of, issues, and lag

• Change: Adds a Data Versioning section to clarify its use.

Magic GitHub syntax to mark associated Issue(s) as resolved when this is merged into the default branch

• Resolves docs: auth keys instructions #295, resolves Small function documentation details updates #287, resolves Reduce doc duplication in general and for version-related params #221, resolves document versions, issues, as_of, and recommendations #199

[JavierMtzRdz]

I added changes to address issues #208 and #288.

Change explanations for reviewer

• Issue Consider changing \dontrun in examples to \donttest #208: \dontrun does not permit examples showing request outputs on the documentation site. It suggests using \donttest.

• Change: I added conditional examples with @examplesIf so they only run when there is internet access and the corresponding API key is available. I did not use \donttest as it is checked by CRAN occasionally. The examples on the documentation website appear when the API key is available. Examples with lengthy outputs are enclosed within \dontrun safeguards.

• Issue Audit all endpoint examples to make sure they actually run as-is #288: Audit all endpoint examples.

• Note: All examples worked. The only relevant comment is that the pub_flusurv example returns data with a warning.

Warning message:
Not all return columns are specified as expected epidata fields
ℹ Unspecified fields season, rate_age_5, rate_age_6, rate_age_7, rate_age_18t29,
rate_age_30t39, rate_age_40t49, rate_age_5t11, rate_age_12t17, rate_age_lt18,
rate_age_gte18, rate_age_1t4, rate_age_gte75, rate_age_0tlt1, rate_race_white,
rate_race_black, rate_race_hisp, rate_race_asian, …, rate_flu_a, and rate_flu_b may
need to be manually converted to more appropriate classes

Magic GitHub syntax to mark associated Issue(s) as resolved when this is merged into the default branch

• Resolves Consider changing \dontrun in examples to \donttest #208, resolves Audit all endpoint examples to make sure they actually run as-is #288

[dshemetov]

Request: the Data Versioning section is good, but can we also add two more examples to the Getting Started vignette to address my suggestion in #199? Specifically of using the issues field and the lag field.

[JavierMtzRdz]

In the last commit, I included examples using the issues and lag arguments in the “Getting Started” vignette and added references to the versioned data vignette in the versioned data documentation section.

[nmdefries]

This looks good to me. I made some small changes to the shared params wording, and updated DESCRIPTION and NEWS.

The examples are now failing, although I didn't change them. Potentially a dependency bump?

[JavierMtzRdz]

There was an example missing a function namespace. It has been fixed.