Merge #5110

5110: Increase margin on deletion of task r=dureuill a=irevoire

# Pull Request

## Related issue
Fixes https://github.com/meilisearch/meilisearch/issues/5077

## What does this PR do?
- Increase the margin we keep to enqueue task deletion

The issue was that we had not enough space on the reserved memory to write both the batch and the deletion task we just enqueued.
We could fix it only for this test as it’s not an issue in production where we have 10GiB of margin, but I thought it wasn’t a bad idea either to increase our margin a bit since we’re effectively writing more to lmdb.


Co-authored-by: Tamo <tamo@meilisearch.com>

crates/index-scheduler/src/lib.rs

@@ -1440,7 +1440,7 @@ impl IndexScheduler {
 
         // if the task doesn't delete anything and 50% of the task queue is full, we must refuse to enqueue the incomming task
         if !matches!(&kind, KindWithContent::TaskDeletion { tasks, .. } if !tasks.is_empty())
-            && (self.env.non_free_pages_size()? * 100) / self.env.info().map_size as u64 > 50
+            && (self.env.non_free_pages_size()? * 100) / self.env.info().map_size as u64 > 40
         {
             return Err(Error::NoSpaceLeftInTaskQueue);
         }