Address broken tests

Tests were failing because they were looking at the finish reason in
every data chunck instead of the last one.

Author: rlazo

firebase-ai/src/test/java/com/google/firebase/ai/DevAPIStreamingSnapshotTests.kt

@@ -42,9 +42,10 @@ internal class DevAPIStreamingSnapshotTests {
       withTimeout(testTimeout) {
         val responseList = responses.toList()
         responseList.isEmpty() shouldBe false
-        responseList.first().candidates.first().finishReason shouldBe FinishReason.STOP
-        responseList.first().candidates.first().content.parts.isEmpty() shouldBe false
-        responseList.first().candidates.first().safetyRatings.isEmpty() shouldBe false
+        responseList.last().candidates.first().let {
+          it.finishReason shouldBe FinishReason.STOP
+          it.content.parts.isEmpty() shouldBe false
+        }
       }
     }
 
@@ -56,10 +57,9 @@ internal class DevAPIStreamingSnapshotTests {
       withTimeout(testTimeout) {
         val responseList = responses.toList()
         responseList.isEmpty() shouldBe false
-        responseList.forEach {
-          it.candidates.first().finishReason shouldBe FinishReason.STOP
-          it.candidates.first().content.parts.isEmpty() shouldBe false
-          it.candidates.first().safetyRatings.isEmpty() shouldBe false
+        responseList.last().candidates.first().let {
+          it.finishReason shouldBe FinishReason.STOP
+          it.content.parts.isEmpty() shouldBe false
         }
       }
     }