Fix docs: validation -> validate for method name #5361

Job	Run time
Run Tests (macos-latest, 3.10)	5m 19s
Run Tests (macos-latest, 3.11)	5m 42s
Run Tests (macos-latest, 3.12)	7m 36s
Run Tests (windows-latest, 3.10)	7m 25s
Run Tests (windows-latest, 3.11)	7m 41s
Run Tests (windows-latest, 3.12)	8m 51s
Run Tests (macos-13, 3.12, pyuvdata_tests)	19m 8s
Performance Benchmark (macos-latest, 3.12)	21s
Performance Benchmark (windows-latest, 3.12)	6m 4s
Performance Benchmark (ubuntu-latest, 3.12)	14s
Performance Benchmark (macos-13, 3.12, pyuvdata_tests)	34s
	1h 8m 55s

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