Remove defunct in.place argument to droplevels() method

[MichaelChirico]

Finishing the deprecation cycle: #6316 -> #6652

[MichaelChirico]

• Progress deprecated option 'datatable.nomatch' to error #6644
• Simplify error for := under with=FALSE #6834
• Remove defunct in.place argument to droplevels() method #6833 👈 (View in Graphite)
• Remove defunct autostart from fread() #6832
• Remove defunct 'logicalAsInt` from fwrite #6831
• master

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.59%. Comparing base (7e41884) to head (38550a4).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6833      +/-   ##
==========================================
- Coverage   98.59%   98.59%   -0.01%     
==========================================
  Files          79       79              
  Lines       14662    14661       -1     
==========================================
- Hits        14456    14455       -1     
  Misses        206      206              

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[github-actions]

Generated via commit 38550a4

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

Task	Duration
R setup and installing dependencies	4 minutes and 30 seconds
Installing different package versions	8 minutes and 3 seconds
Running and plotting the test cases	2 minutes and 18 seconds

[ben-schwen]

LGTM TY