v1.2.1

DataFrames v1.2.1

Diff since v1.2.0

Closed issues:

• "transform" function not available (#2815)
• How to change the value of a cell to a different data type? (#2816)
• dropmissing! creates weird memory bugs/errors on 1.7 and 1.6 (#2819)

Merged pull requests:

• Document GroupedDataFrame consistency check (#2811) (@bkamins)
• fix delete! for versions of Julia 1.6.2 or earlier (#2820) (@bkamins)