fix(prover): Do not exit on missing watcher data. (#3119)

## What ❔

Do not exit on missing watcher data.
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## Why ❔

To fix always exiting in `scaler_period` after start due to missing
data.

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## Checklist

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- [x] PR title corresponds to the body of PR (we generate changelog
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- [ ] Tests for the changes have been added / updated.
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lint`.

ref ZKD-1855

prover/crates/bin/prover_autoscaler/src/global/scaler.rs

@@ -305,7 +305,10 @@ impl Task for Scaler {
         let queue = self.queuer.get_queue().await.unwrap();
 
         let guard = self.watcher.data.lock().await;
-        watcher::check_is_ready(&guard.is_ready)?;
+        if let Err(err) = watcher::check_is_ready(&guard.is_ready) {
+            tracing::warn!("Skipping Scaler run: {}", err);
+            return Ok(());
+        }
 
         for (ns, ppv) in &self.namespaces {
             let q = queue.queue.get(ppv).cloned().unwrap_or(0);