Fix array splat deprecation warning

Fixes following warning:
Passing an explicit array value to a Scala varargs method is deprecated (since 2.13.0) and will result in a defensive copy; Use the more efficient non-copying ArraySeq.unsafeWrapArray or an explicit toIndexedSeq call

Change-Id: I036e494280f3f3ce8720ef3987d697d8e1f77df7

src/main/scala/com/googlesource/gerrit/plugins/analytics/Contributors.scala

diff --git a/src/main/scala/com/googlesource/gerrit/plugins/analytics/Contributors.scala b/src/main/scala/com/googlesource/gerrit/plugins/analytics/Contributors.scala
index 37006ca..5b4f172 100644
--- a/src/main/scala/com/googlesource/gerrit/plugins/analytics/Contributors.scala
+++ b/src/main/scala/com/googlesource/gerrit/plugins/analytics/Contributors.scala
@@ -180,7 +180,7 @@
   def apply(statisticsHandler: Statistics)(uca: AggregatedUserCommitActivity)
   : Iterable[UserActivitySummary] = {
 
-    statisticsHandler.forCommits(uca.getIds: _*).map { stat =>
+    statisticsHandler.forCommits(uca.getIds.toIndexedSeq: _*).map { stat =>
       val maybeBranches =
         uca.key.branch.fold(Array.empty[String])(Array(_))