Increase time buffer to reduce flakiness in filter age test

Added a larger time buffer to the filter age difference check in
testFilterAgeIncreasesBetweenPackets to mitigate potential flakiness
caused by delays in the second ping reply.

Bug: 347641209
Test: TH
Change-Id: I1a7698297bf36a295b1428c92bf83158539bb867
diff --git a/tests/cts/net/src/android/net/cts/ApfIntegrationTest.kt b/tests/cts/net/src/android/net/cts/ApfIntegrationTest.kt
index 086f0e7..d233fee 100644
--- a/tests/cts/net/src/android/net/cts/ApfIntegrationTest.kt
+++ b/tests/cts/net/src/android/net/cts/ApfIntegrationTest.kt
@@ -554,6 +554,7 @@
         buffer = ByteBuffer.wrap(readProgram(), counterRegion, 4 /* length */)
         val filterAgeSeconds = buffer.getInt()
         // Assert that filter age has increased, but not too much.
-        assertThat(filterAgeSeconds - filterAgeSecondsOrig).isEqualTo(5)
+        val timeDiff = filterAgeSeconds - filterAgeSecondsOrig
+        assertThat(timeDiff).isAnyOf(5, 6)
     }
 }