Rename no_tab_linter to whitespace_linter

[MichaelChirico]

Closes #1954

[codecov-commenter]

Codecov Report

Merging #1955 (e0b64f3) into main (fb294cc) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head e0b64f3 differs from pull request most recent head 34efc8a. Consider uploading reports for the commit 34efc8a to get more accurate results

@@           Coverage Diff           @@
##             main    #1955   +/-   ##
=======================================
  Coverage   98.95%   98.95%           
=======================================
  Files         113      113           
  Lines        4966     4972    +6     
=======================================
+ Hits         4914     4920    +6     
  Misses         52       52           

Impacted Files	Coverage Δ
R/lintr-deprecated.R	100.00% <100.00%> (ø)

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[AshesITR]

Not sure whether we should explicitly state future planned development in the docs.

[MichaelChirico]

Not sure whether we should explicitly state future planned development in the docs.

Do you mean in NEWS? In ?whitespace_linter, we have "Currently, only supports linting in the presence of tabs." which hints at something being done later but gives no specifics/commitments. I think that's OK; submitting for now but feel free to follow-up