Working apalis cron and worker with 0.6.0-rc.5

Also renamed `pool` variables throughout codebase to `db` for clarity.

src/jobs/mod.rs

@@ -1,11 +1,8 @@
-use apalis::prelude::*;
 use serde::{Deserialize, Serialize};
 
+mod crawl_feed;
+
 #[derive(Debug, Deserialize, Serialize, Clone)]
 pub enum AsyncJob {
     HelloWorld(String),
 }
-
-impl Job for AsyncJob {
-    const NAME: &'static str = "apalis::AsyncJob";
-}