Merge #2982

2982: Adapt task queries to account for special index swap rules r=irevoire a=loiclec

# Pull Request

## Related issue
Fixes https://github.com/meilisearch/meilisearch/issues/2970 

## What does this PR do?
- Replace the `get_tasks` method with a `get_tasks_from_authorized_indexes` which returns the list of tasks matched by the query **from the point of view of the user**. That is, it takes into consideration the list of authorised indexes as well as the special case of `IndexSwap` which should not be returned if an index_uid is specified or if any of its associated indexes are not authorised.
- Adapt the code in other places following this change
- Add some tests
- Also the method `get_task_ids_from_authorized_indexes` now takes a read transaction as argument. This is because we want to make sure that the implementation of `get_tasks_from_authorized_indexes` only uses one read transaction. Otherwise, we could (1) get a list of task ids matching the query, then (2) one of these task ids is deleted by a taskDeletion task, and finally (3) we try to get the `Task`s associated with each returned task ids, and get a `CorruptedTaskQueue` error.



Co-authored-by: Loïc Lecrenier <loic.lecrenier@me.com>

meilisearch-auth/src/lib.rs

@@ -215,6 +215,27 @@ impl SearchRules {
             }
         }
     }
+
+    /// Return the list of indexes such that `self.is_index_authorized(index) == true`,
+    /// or `None` if all indexes satisfy this condition.
+    pub fn authorized_indexes(&self) -> Option<Vec<String>> {
+        match self {
+            SearchRules::Set(set) => {
+                if set.contains("*") {
+                    None
+                } else {
+                    Some(set.iter().cloned().collect())
+                }
+            }
+            SearchRules::Map(map) => {
+                if map.contains_key("*") {
+                    None
+                } else {
+                    Some(map.keys().cloned().collect())
+                }
+            }
+        }
+    }
 }
 
 impl IntoIterator for SearchRules {