Convert some more uses of the Java stream API to native Kotlin idioms. (#1982)

Author: JonathanLennox

jvb/src/main/kotlin/org/jitsi/videobridge/cc/allocation/AllocationSettings.kt

@@ -137,7 +137,7 @@ internal class AllocationSettingsWrapper(private val useSourceNames: Boolean) {
             // Convert endpoint IDs to source names
             if (!useSourceNames) {
                 newConstraints = HashMap(it.size)
-                it.entries.stream().forEach {
+                it.entries.forEach {
                         entry ->
                     newConstraints[endpointIdToSourceName(entry.key)] = entry.value
                 }

jvb/src/main/kotlin/org/jitsi/videobridge/xmpp/config/XmppClientConnectionConfig.kt

@@ -52,11 +52,11 @@ class XmppClientConnectionConfig private constructor() {
      * The interval at which presence updates (with updates stats/status) are published. Allow to be overridden by
      * legacy-style "stats-transports" config.
      */
-    val presenceInterval: Duration = StatsManagerConfig.config.transportConfigs.stream()
-        .filter { tc -> tc is StatsTransportConfig.MucStatsTransportConfig }
+    val presenceInterval: Duration = StatsManagerConfig.config.transportConfigs
+        .filterIsInstance<StatsTransportConfig.MucStatsTransportConfig>()
         .map(StatsTransportConfig::interval)
-        .findFirst()
-        .orElse(presenceIntervalProperty)
+        .firstOrNull()
+        ?: presenceIntervalProperty
 
     /**
      * Whether to filter the statistics.