sql: make all queries persistent and update to upstream sqlx

&str queries are not persistent by default.  To make queries persistent,
they have to be constructed with sqlx::query.

Upstream sqlx does not contain the change that make all queries
persistent, but it is not needed anymore. but

src/location.rs

@@ -401,7 +401,10 @@ fn is_marker(txt: &str) -> bool {
 
 /// Deletes all locations from the database.
 pub async fn delete_all(context: &Context) -> Result<(), Error> {
-    context.sql.execute("DELETE FROM locations;").await?;
+    context
+        .sql
+        .execute(sqlx::query("DELETE FROM locations;"))
+        .await?;
     context.emit_event(EventType::LocationChanged(None));
     Ok(())
 }