avoid SocketTimeoutException by higher interval

app/src/main/java/com/nextcloud/talk/webrtc/WebSocketInstance.kt

@@ -533,7 +533,7 @@ class WebSocketInstance internal constructor(conversationUser: User, connectionU
         private const val TAG = "WebSocketInstance"
         private const val NORMAL_CLOSURE = 1000
         private const val ONE_SECOND: Long = 1000
-        private const val PING_INTERVAL_SECONDS: Long = 10
+        private const val PING_INTERVAL_SECONDS: Long = 30
 
         // Dedicated client with pings, so half-open WebSocket connections
         // (e.g. after a WiFi to cellular switch without TCP reset) fail and trigger the reconnect path.

app/src/test/java/com/nextcloud/talk/webrtc/WebSocketInstanceSignalingClientTest.kt

@@ -29,7 +29,7 @@ class WebSocketInstanceSignalingClientTest {
         // hardcoded on purpose: fails if the ping interval in WebSocketInstance changes or is removed
         assertEquals(
             "signaling WebSocket client must send pings to detect half-open connections",
-            10_000,
+            30_000,
             signalingClient.pingIntervalMillis
         )
     }