[gpuCI] Forward-merge branch-0.19 to branch-0.20 [skip ci]#7797

Merged

GPUtester merged 2 commits intobranch-0.20from branch-0.19

Mar 31, 2021

+832-298

Commits on Mar 31, 2021

Struct hashing support for SerialMurmur3 and SparkMurmur3 (#7714 )
jlowe
authored
Fix inplace update of data and add Series.update (#7201 )
galipremsagar
authored