made todo labels consistent

[badasahog]

I think todo labels are the thing you're you're most likely to search code for, so making them all appear the same would seem pertinant.

It was very inconsistent, so I settled on todo:

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
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Additional details and impacted files

@@            Coverage Diff            @@
##             master    #7113   +/-   ##
=========================================
  Coverage          ?   98.79%           
=========================================
  Files             ?       81           
  Lines             ?    15254           
  Branches          ?        0           
=========================================
  Hits              ?    15070           
  Misses            ?      184           
  Partials          ?        0           

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[github-actions]

• HEAD=todoRename slower P<0.001 for isoweek improved in #7144
  

Generated via commit 9ee598f

Download link for the artifact containing the test results: ↓ atime-results.zip

Task	Duration
R setup and installing dependencies	4 minutes and 45 seconds
Installing different package versions	9 minutes and 53 seconds
Running and plotting the test cases	2 minutes and 37 seconds

[MichaelChirico]

Related: #678

[badasahog]

@MichaelChirico this should make that work, right? or do you prefer a different syntax?

[MichaelChirico]

We can worry about the exact syntax later -- once we have something consistent, at least, a find-and-replace version becomes a lot easier.

That said, this PR will also sit idle for a while in the spirit of avoiding merge conflicts 🫤

[MichaelChirico]

Here are the unique, open, non-draft PRs touching files also touched by this PR: #6965, #6640, #6595, #6111, #5907, #5898, #5896, #5895, #5893, #5892, #5890, #5692, #5682, #5576, #5575, #5269, #5168, #5167, #4978, #4585, #4372, #4370