update sqlparser

[SingingBush]

When I forked the repo it wouldn't build due to:

error[E0308]: mismatched types
  --> rdbc-postgres/src/lib.rs:73:34
   |
73 |                         keyword: "".to_owned(),
   |                                  ^^^^^^^^^^^^^ expected enum `Keyword`, found struct `std::string::String`

this seems to sort it