Replace MovieLens loaders with load_movielens function #457

Job	Run time
Non-JIT test coverage	44s
FunkSVD tests on Python 3.10	45s
Minimal dependency tests for FunkSVD	34s
FunkSVD tests on Python 3.11	36s
Conda Python 3.10 on ubuntu-latest	40s
FunkSVD tests on Python 3.12	39s
Conda Python 3.10 on macos-latest	41s
Implicit bridge tests on Python 3.10	43s
Conda Python 3.10 on windows-latest	3m 7s
Implicit bridge tests on Python 3.11	40s
Conda Python 3.11 on ubuntu-latest	31s
Minimal dependency tests for Implicit	30s
Minimal dependency tests	24s
Implicit bridge tests on Python 3.12	53s
Conda Python 3.11 on macos-latest	36s
Conda Python 3.11 on windows-latest	2m 59s
Conda Python 3.12 on ubuntu-latest	34s
Vanilla Python 3.10 on ubuntu-latest	26s
Conda Python 3.12 on macos-latest	35s
Demos, examples, and docs	1m 12s
Vanilla Python 3.10 on macos-latest	26s
Conda Python 3.12 on windows-latest	3m 0s
Vanilla Python 3.11 on ubuntu-latest	32s
Vanilla Python 3.11 on macos-latest	24s
Evaluation-based tests	52s
Vanilla Python 3.12 on ubuntu-latest	32s
HPF bridge tests on Python 3.10	49s
Vanilla Python 3.12 on macos-latest	32s
HPF bridge tests on Python 3.11	57s
HPF bridge tests on Python 3.12	55s
Test suite results	1s
	26m 49s

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