Support hex string literal

[ShiKaiWi]

Which issue does this PR close?

Closes #6764 .

Rationale for this change

Datafusion supports the binary data type, but there is no way to insert binary data or query with binary data in a predicate through a sql. And this is caused by missing conversion from sqlparser::ast::Value::HexStringLiteral to datafusion_expr::Expr::Literal(ScalarValue::Binary).

What changes are included in this PR?

Support the conversion from sqlparser::ast::Value::HexStringLiteral to datafusion_expr::Expr::Literal(ScalarValue::Binary).

Are these changes tested?

Add a unit test for hex string literal decoding.

Are there any user-facing changes?

Now, the sql including hex string literal, e.g. X'FF01', can be processed and treated as a binary data by datafusion.

[jackwener]

Thanks @ShiKaiWi

[jackwener]

Can you add a sqllogicaltest for this case? @ShiKaiWi
You can see directory datafusion/core/tests/sqllogictests

[alamb]

Thank you @ShiKaiWi -- this looks great

The only thing I think it needs are some end to end tests in .slt -- I made some in #6770 which we can merge after this one.

[alamb]

Something about this PR appears to be problematic:

@tustvold is that what you were trying to fix?

[tustvold]

@tustvold is that what you were trying to fix?

Yes, I accidentally force pushed main, it should be reverted now and #6775 should prevent this in future, but the PR dialog appears to be a tad confused by this. Will try closing and reopening

[alamb]

#6770 is now ready for review too (with some basic .slt tests)