test(okhttp): widen SurgeDns stale-refresh TTL to defeat double-expiry race

The 1ms positiveTtlMs let the second refreshed entry expire again
between the post-refresh assertion and the cache-hit lookup that
followed, triggering an extra background refresh that broke the
calls=2 invariant on slow CI runners. 100ms TTL with sleep(150)
keeps the expiry boundary clearly outside the assertion window.

amethyst/src/test/java/com/vitorpamplona/amethyst/service/okhttp/SurgeDnsTest.kt

@@ -141,16 +141,19 @@ class SurgeDnsTest {
                 responses.get()
             }
         val syncRefresh = Executor { it.run() }
+        // 100ms TTL gives both branches enough headroom on slow CI: Thread.sleep(150) reliably
+        // expires the first entry, and the post-refresh entry can't expire between the two
+        // assertions below (microseconds apart on any sane runner).
         val dns =
             SurgeDns(
                 delegate = upstream,
-                positiveTtlMs = 1,
+                positiveTtlMs = 100,
                 positiveTtlJitterMs = 0,
                 refreshExecutor = syncRefresh,
             )
 
         assertEquals(listOf(ip("1.2.3.4")), dns.lookup("a.example"))
-        Thread.sleep(20)
+        Thread.sleep(150)
 
         // Upstream now returns a new IP. The next lookup should still serve the OLD IP
         // immediately, while the synchronous executor performs the refresh inline.