Allow updater to check for updates after downloading one (#30969)

Closes https://github.com/zed-industries/zed/issues/8968

This PR addresses the following scenario:

1. User's Zed polls for an update, finds one, and installs it
2. User doesn't immediately restart Zed, a new update is released, and
the previous version of Zed would stop polling (ignoring the new update)
3. User eventually restarts Zed and is immediately prompted to install
another update

With this change, the auto-updater will continue polling for and
installing new versions even after an initial update is found, reducing
update prompts on restart.

---

This PR does not address the following scenario:

1. User's Zed polls for an update, finds one, and installs it
2. Another update is released before the next scheduled polling interval
3. User restarts Zed and is immediately prompted to install the newer
update

Release Notes:

- Improved the auto-updater to continue checking for updates even after
finding and installing an initial update. This reduces situations where
users are prompted to install another update immediately after
restarting from a previous update.

Co-authored-by: Ben Kunkle <Ben.kunkle@gmail.com>

crates/activity_indicator/src/activity_indicator.rs

@@ -485,7 +485,7 @@ impl ActivityIndicator {
                         this.dismiss_error_message(&DismissErrorMessage, window, cx)
                     })),
                 }),
-                AutoUpdateStatus::Updated { binary_path } => Some(Content {
+                AutoUpdateStatus::Updated { binary_path, .. } => Some(Content {
                     icon: None,
                     message: "Click to restart and update Zed".to_string(),
                     on_click: Some(Arc::new({