[Enhancement] Garbage collection of unused data on remote storage backend (#10731)

* [Feature](cold_on_s3) support unused remote rowset gc

* return aborted when skip drop tablet

* perform unused remote rowset gc

fe/fe-core/src/main/java/org/apache/doris/clone/BackendLoadStatistic.java

@@ -283,10 +283,12 @@ public class BackendLoadStatistic {
         // Else if capacity used percent > 75%, set capacityCoefficient to 1.
         // Else, capacityCoefficient changed smoothly from 0.5 to 1 with used capacity increasing
         // Function: (2 * usedCapacityPercent - 0.5)
-        loadScore.capacityCoefficient = usedCapacityPercent < 0.5 ? 0.5
-                : (usedCapacityPercent > Config.capacity_used_percent_high_water ? 1.0
-                        : (2 * usedCapacityPercent - 0.5));
-        loadScore.replicaNumCoefficient = 1 - loadScore.capacityCoefficient;
+        if (!Config.be_rebalancer_fuzzy_test) {
+            loadScore.capacityCoefficient = usedCapacityPercent < 0.5 ? 0.5
+                    : (usedCapacityPercent > Config.capacity_used_percent_high_water ? 1.0
+                            : (2 * usedCapacityPercent - 0.5));
+            loadScore.replicaNumCoefficient = 1 - loadScore.capacityCoefficient;
+        }
         loadScore.score = capacityProportion * loadScore.capacityCoefficient
                 + replicaNumProportion * loadScore.replicaNumCoefficient;
 

fe/fe-core/src/main/java/org/apache/doris/common/Config.java

@@ -1685,7 +1685,7 @@ public class Config extends ConfigBase {
      * It's used to test the reliability in single replica case when tablet scheduling are frequent.
      * Default is false.
      */
-    @ConfField(mutable = false, masterOnly = true)
+    @ConfField(mutable = true, masterOnly = true)
     public static boolean be_rebalancer_fuzzy_test = false;
 
     /**