Resolve more linter warnings

src/utils.rs

@@ -9,7 +9,10 @@ pub fn unix_timestamp() -> u32 {
     let since_the_epoch = start
         .duration_since(UNIX_EPOCH)
         .expect("Time went backwards");
-    since_the_epoch.as_secs() as u32
+    since_the_epoch
+        .as_secs()
+        .try_into()
+        .expect("Linux time no longer fits into 32 bits.")
 }
 
 pub fn read_base64(path: &str) -> Bytes {