Revert "DData: Fix BCL update causing DeltaPropagationSelector throwi…

…ng Index…" (#7483)

This reverts commit 5c7c967.

src/contrib/cluster/Akka.DistributedData/DeltaPropagationSelector.cs

@@ -70,9 +70,7 @@ public ImmutableDictionary<Address, DeltaPropagation> CollectPropagations()
                 else
                 {
                     var i = (int)(_deltaNodeRoundRobinCounter % all.Length);
-                    var endIndex = i + sliceSize;
-                    if (endIndex > all.Length) endIndex = all.Length;
-                    slice = all[i..endIndex];
+                    slice = all.Slice(i, sliceSize).ToImmutableArray();
 
                     if (slice.Length != sliceSize)
                         slice = slice.AddRange(all.Take(sliceSize - slice.Length));