fix(quic): replace deprecated lock with split locks in QlogObserverTest

The post-handshake status check uses lifecycleLock (status is guarded
by lifecycleLock per the lock-split refactor); the malformed-datagram
test uses streamsLock since feedDatagram requires streamsLock.

quic/src/commonTest/kotlin/com/vitorpamplona/quic/observability/QlogObserverTest.kt

@@ -53,7 +53,7 @@ class QlogObserverTest {
         runBlocking {
             val client = handshakedClient(QlogObserver.NoOp)
             // Drive a tiny operation post-handshake.
-            client.lock.withLock {
+            client.lifecycleLock.withLock {
                 // No-op — just confirm we can still take the lock.
                 assertEquals(QuicConnection.Status.CONNECTED, client.status)
             }
@@ -141,7 +141,7 @@ class QlogObserverTest {
                     0x00, // pn byte
                     0x00, // payload byte (will fail AEAD)
                 )
-            client.lock.withLock {
+            client.streamsLock.withLock {
                 feedDatagram(client, garbage, nowMillis = 1L)
             }
             val drops = recorder.events.filter { it.name == "packetDropped" }