Fix deprecated argument, remove unnecessary env var

[github-actions[bot]]

(benchmark 4556367837 / attempt 1) Base results / Our results / Change	Model	Size	Dump Time	Load Time
sklearn rf 20M	20.8 MiB / 3.0 MiB / 6.87 x	0.02 s / 0.05 s / 2.35 x	0.02 s / 0.03 s / 1.86 x
sklearn rf 20M lzma	6.5 MiB / 2.0 MiB / 3.26 x	14.31 s / 1.48 s / 0.10 x	0.67 s / 0.22 s / 0.33 x
sklearn rf 200M	212.3 MiB / 30.6 MiB / 6.94 x	0.16 s / 0.40 s / 2.55 x	0.19 s / 0.36 s / 1.87 x
sklearn rf 200M lzma	47.4 MiB / 14.6 MiB / 3.24 x	117.66 s / 21.51 s / 0.18 x	5.28 s / 1.74 s / 0.33 x
sklearn rf 1G	1157.5 MiB / 166.8 MiB / 6.94 x	1.19 s / 2.08 s / 1.75 x	1.16 s / 1.67 s / 1.44 x
sklearn rf 1G lzma	258.1 MiB / 98.1 MiB / 2.63 x	620.28 s / 128.94 s / 0.21 x	28.45 s / 10.27 s / 0.36 x
sklearn gb 2M	2.2 MiB / 1.1 MiB / 2.08 x	0.04 s / 0.33 s / 8.18 x	0.04 s / 0.15 s / 3.44 x
sklearn gb 2M lzma	0.6 MiB / 0.2 MiB / 3.81 x	1.18 s / 0.52 s / 0.44 x	0.11 s / 0.17 s / 1.61 x
lgbm gbdt 2M	2.6 MiB / 1.0 MiB / 2.78 x	0.12 s / 0.33 s / 2.77 x	0.02 s / 0.19 s / 11.49 x
lgbm gbdt 2M lzma	0.9 MiB / 0.5 MiB / 1.90 x	1.91 s / 0.69 s / 0.36 x	0.11 s / 0.22 s / 2.12 x
lgbm gbdt 5M	5.3 MiB / 1.9 MiB / 2.81 x	0.22 s / 0.61 s / 2.72 x	0.03 s / 0.37 s / 12.18 x
lgbm gbdt 5M lzma	1.7 MiB / 0.8 MiB / 1.96 x	4.61 s / 1.41 s / 0.31 x	0.19 s / 0.45 s / 2.42 x
lgbm gbdt 20M	22.7 MiB / 7.6 MiB / 3.00 x	0.92 s / 2.49 s / 2.69 x	0.13 s / 1.52 s / 11.39 x
lgbm gbdt 20M lzma	6.3 MiB / 3.0 MiB / 2.09 x	24.99 s / 6.45 s / 0.26 x	0.74 s / 1.81 s / 2.45 x
lgbm gbdt 100M	101.1 MiB / 33.0 MiB / 3.06 x	3.96 s / 11.32 s / 2.86 x	0.64 s / 51.51 s / 80.20 x
lgbm gbdt 100M lzma	25.6 MiB / 10.6 MiB / 2.41 x	117.34 s / 29.92 s / 0.26 x	3.05 s / 69.62 s / 22.85 x
lgbm rf 10M	10.9 MiB / 3.2 MiB / 3.46 x	0.45 s / 0.99 s / 2.22 x	0.07 s / 0.68 s / 10.32 x
lgbm rf 10M lzma	0.7 MiB / 0.4 MiB / 1.85 x	2.42 s / 1.21 s / 0.50 x	0.14 s / 0.70 s / 4.83 x