Fix missing arguments nullability in FunctionMetadata

[weijiii]

Summary

• Should fix the issues in some test failures #149
• Related concern was raised here
• Trino engine does not invoke function when non-nullable arguments receive null value; this is determined by FunctionMetadata#functionNullability
• FunctionMetadata#argumentNullability expects Boolean object
• Revert changes in TestFileLookUp, since Trino actually throws NullPointerException in this case

[weijiii]

@yiqiangin Can you please check if the other isTrinoTest usage are needed and request changes? Thanks.

[yiqiangin]

@yiqiangin Can you please check if the other isTrinoTest usage are needed and request changes? Thanks.

Other usages of isTrinoTest are still needed as they are not related to null argument.
Also With this code change, all tests in standard-udf-userinterfacelookup and standard-udfs-dali-udfs can pass now.