sqlx-macros: fix handling of invalid idents

add regression test with Trybuild

fix lint warnings as otherwise Trybuild wanted to include them

sqlx-core/src/postgres/arguments.rs

@@ -1,6 +1,6 @@
 use byteorder::{ByteOrder, NetworkEndian};
 
-use crate::arguments::{Arguments, IntoArguments};
+use crate::arguments::Arguments;
 use crate::encode::{Encode, IsNull};
 use crate::io::BufMut;
 use crate::types::HasSqlType;

sqlx-core/src/postgres/protocol/close.rs

@@ -1,3 +1,4 @@
+#![allow(dead_code)]
 use crate::io::BufMut;
 use crate::postgres::protocol::Encode;
 use byteorder::NetworkEndian;

sqlx-core/src/postgres/protocol/mod.rs

@@ -19,6 +19,7 @@ mod parse;
 mod password_message;
 mod query;
 mod sasl;
+#[cfg_attr(not(feature = "tls"), allow(unused_imports, dead_code))]
 mod ssl_request;
 mod startup_message;
 mod statement;