[rust] Fix NDArrayTests failure on cuda

[xyang16]

Description

Brief description of what this PR is about

Fix NDArrayTests failure on cuda

1. ai.djl.engine.rust.NDArrayTests.testExpandDim: This is candle bug. I raised an issue in candle. I will add the code back once it's fixed.

ai.djl.engine.EngineException: DriverError(CUDA_ERROR_INVALID_VALUE, "invalid argument")
	at app//ai.djl.engine.rust.RustLibrary.contentEqual(Native Method)
	at app//ai.djl.engine.rust.RsNDArray.contentEquals(RsNDArray.java:368)
	at app//ai.djl.engine.rust.RsNDArray.equals(RsNDArray.java:1615)
	at app//org.testng.Assert.areEqualImpl(Assert.java:180)
	at app//org.testng.Assert.assertEqualsImpl(Assert.java:148)
	at app//org.testng.Assert.assertEquals(Assert.java:132)
	at app//org.testng.Assert.assertEquals(Assert.java:644)
	at app//ai.djl.engine.rust.NDArrayTests.testExpandDim(NDArrayTests.java:225)

2. ai.djl.engine.rust.NDArrayTests.testToDataType: Changed to cast int32 to float16 since cast_i64_f16 is not supported.

ai.djl.engine.EngineException: Cuda(Load { cuda: DriverError(CUDA_ERROR_NOT_FOUND, "named symbol not found"), module_name: "cast_i64_f16" })
	at app//ai.djl.engine.rust.RustLibrary.toDataType(Native Method)
	at app//ai.djl.engine.rust.RsNDArray.toType(RsNDArray.java:175)
	at app//ai.djl.engine.rust.RsNDArray.toType(RsNDArray.java:35)
	at app//ai.djl.engine.rust.NDArrayTests.testToDataType(NDArrayTests.java:110)