Update Scala to 2.13.10

Change-Id: I6e9fd3d045cb2f48d489a4e9d045a3cdcb16fe67
diff --git a/build.sbt b/build.sbt
index 23b5f1d..d24135d 100644
--- a/build.sbt
+++ b/build.sbt
@@ -16,7 +16,7 @@
     resolvers += Resolver.mavenLocal,
     version := gerritApiVersion,
 
-    scalaVersion := "2.11.12",
+    scalaVersion := "2.13.10",
 
     libraryDependencies ++= Seq(
       "io.fabric8" % "gitective-core" % "0.9.54"
diff --git a/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/BranchesExtractor.scala b/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/BranchesExtractor.scala
index 9703da1..de45f80 100644
--- a/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/BranchesExtractor.scala
+++ b/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/BranchesExtractor.scala
@@ -19,18 +19,18 @@
 import org.eclipse.jgit.lib.{Constants, ObjectId, Repository}
 import org.eclipse.jgit.revwalk.RevWalk
 
-import scala.collection.JavaConversions._
+import scala.jdk.CollectionConverters._
 
 case class BranchesExtractor(repo: Repository) {
   lazy val branchesOfCommit: Map[ObjectId, Set[String]] = {
 
     use(new Git(repo)) { git =>
-      git.branchList.call.foldLeft(Map.empty[ObjectId, Set[String]]) { (branchesAcc, ref) =>
+      git.branchList.call.asScala.foldLeft(Map.empty[ObjectId, Set[String]]) { (branchesAcc, ref) =>
         val branchName = ref.getName.drop(Constants.R_HEADS.length)
 
         use(new RevWalk(repo)) { rw: RevWalk =>
           rw.markStart(rw.parseCommit(ref.getObjectId))
-          rw.foldLeft(branchesAcc) { (thisBranchAcc, rev) =>
+          rw.asScala.foldLeft(branchesAcc) { (thisBranchAcc, rev) =>
             val sha1 = rev.getId
             thisBranchAcc.get(sha1) match {
               case Some(set) => thisBranchAcc + (sha1 -> (set + branchName))
diff --git a/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/CommitsStatisticsLoader.scala b/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/CommitsStatisticsLoader.scala
index 6adb617..c9478b2 100644
--- a/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/CommitsStatisticsLoader.scala
+++ b/src/main/scala/com/googlesource/gerrit/plugins/analytics/common/CommitsStatisticsLoader.scala
@@ -26,9 +26,9 @@
 import org.eclipse.jgit.revwalk.RevWalk
 import org.eclipse.jgit.treewalk.{CanonicalTreeParser, EmptyTreeIterator}
 import org.eclipse.jgit.util.io.DisabledOutputStream
-import scala.compat.java8.OptionConverters._
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
+import scala.jdk.OptionConverters._
 import scala.util.matching.Regex
 
 class CommitsStatisticsLoader @Inject() (
@@ -45,7 +45,7 @@
     val objectId = cacheKey.commitId
     val nameKey = Project.nameKey(cacheKey.projectName)
     val commentInfoList: Seq[CommentLinkInfo] =
-      if(config.isExtractIssues) projectCache.get(nameKey).asScala.toList.flatMap(_.getCommentLinks.asScala) else Seq.empty
+      if(config.isExtractIssues) projectCache.get(nameKey).toScala.toList.flatMap(_.getCommentLinks.asScala) else Seq.empty
     val replacers = commentInfoList.map(info =>
       Replacer(
         info.`match`.r,
diff --git a/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/CommitStatisticsCommentLinkSpec.scala b/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/CommitStatisticsCommentLinkSpec.scala
index 2e5b756..9266b07 100644
--- a/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/CommitStatisticsCommentLinkSpec.scala
+++ b/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/CommitStatisticsCommentLinkSpec.scala
@@ -24,7 +24,7 @@
 import org.scalatest.flatspec.AnyFlatSpecLike
 import org.scalatest.matchers.should.Matchers
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 @UseLocalDisk
 class CommitStatisticsCommentLinkSpec extends AnyFlatSpecLike with GerritTestDaemon with TestCommitStatisticsNoCache with Matchers with Inside {
diff --git a/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/ContributorsServiceSpec.scala b/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/ContributorsServiceSpec.scala
index dea1ef8..a5d5558 100644
--- a/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/ContributorsServiceSpec.scala
+++ b/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/ContributorsServiceSpec.scala
@@ -26,7 +26,7 @@
 import org.scalatest.flatspec.AnyFlatSpecLike
 import org.scalatest.matchers.should.Matchers
 
-import scala.collection.JavaConverters._
+import scala.jdk.CollectionConverters._
 
 @UseLocalDisk
 class ContributorsServiceSpec extends AnyFlatSpecLike with Matchers with GerritTestDaemon with Inside {