Treat position bias via GAM in LambdaMART #7245

Job	Run time
r-package (ubuntu-latest, gcc, R 3.6, cmake)	13m 9s
r-package (ubuntu-latest, gcc, R 4.2, cmake)	14m 25s
r-package (ubuntu-latest, clang, R 3.6, cmake)	12m 6s
r-package (ubuntu-latest, clang, R 4.2, cmake)	18m 0s
r-package (macOS-latest, gcc, R 4.2, cmake)	12m 20s
r-package (macOS-latest, clang, R 4.2, cmake)	17m 50s
r-package (windows-latest, MINGW, R 3.6, cmake)	19m 3s
r-package (windows-latest, MINGW, R 4.2, cmake)	19m 56s
r-package (windows-2019, MSVC, R 3.6, cmake)	13m 59s
r-package (windows-2022, MSVC, R 4.2, cmake)	17m 16s
r-package (windows-latest, MINGW, R 3.6, cran)	21m 44s
r-package (windows-latest, MINGW, R 4.2, cran)	23m 45s
r-package (ubuntu-latest, gcc, R 4.2, cran)	20m 8s
r-package (macOS-latest, clang, R 4.2, cran)	23m 53s
r-rchk (ubuntu-latest, gcc, R 4.2, cran)	13m 19s
r-package (debian, R-devel, clang)	18m 42s
r-sanitizers (ubuntu-latest, R-devel, gcc ASAN/UBSAN)	21m 28s
r-sanitizers (ubuntu-latest, R-devel, clang ASAN/UBSAN)	31m 23s
all-r-package-jobs-successful	5s
	5h 32m 31s

Provide feedback