refactor(core): deprecate PgConnectionInfo

Signed-off-by: Atkins Chang <atkinschang@gmail.com>

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

@@ -65,6 +65,11 @@ pub struct PgConnection {
 }
 
 impl PgConnection {
+    /// the version number of the server in `libpq` format
+    pub fn server_version_num(&self) -> Option<u32> {
+        self.stream.server_version_num
+    }
+
     // will return when the connection is ready for another query
     async fn wait_until_ready(&mut self) -> Result<(), Error> {
         if !self.stream.wbuf.is_empty() {
@@ -178,19 +183,24 @@ impl Connection for PgConnection {
     }
 }
 
+#[deprecated(since = "0.5.7")]
 pub trait PgConnectionInfo {
     /// the version number of the server in `libpq` format
+    #[deprecated(
+        since = "0.5.7",
+        note = "please use `server_version_num` from impl instead"
+    )]
     fn server_version_num(&self) -> Option<u32>;
 }
 
 impl PgConnectionInfo for PgConnection {
     fn server_version_num(&self) -> Option<u32> {
-        self.stream.server_version_num
+        self.server_version_num()
     }
 }
 
 impl PgConnectionInfo for crate::pool::PoolConnection<Postgres> {
     fn server_version_num(&self) -> Option<u32> {
-        self.stream.server_version_num
+        self.server_version_num()
     }
 }