fix: correct a couple places from the recent column metadata changes

sqlx-core/src/mssql/protocol/col_meta_data.rs

@@ -29,6 +29,7 @@ pub(crate) struct ColumnData {
 }
 
 bitflags! {
+    #[cfg_attr(feature = "offline", derive(serde::Serialize, serde::Deserialize))]
     pub struct Flags: u16 {
         // Its value is 1 if the column is nullable.
         const NULLABLE = 0x0001;

sqlx-macros/src/query/mod.rs

@@ -161,7 +161,7 @@ trait StatementInfoExt: serde::Serialize + serde::de::DeserializeOwned {}
 
 #[cfg(feature = "offline")]
 impl<DB: Database> StatementInfoExt for StatementInfo<DB> where
-    Describe<DB>: serde::Serialize + serde::de::DeserializeOwned
+    StatementInfo<DB>: serde::Serialize + serde::de::DeserializeOwned
 {
 }