binderRpcTest ThreadPoolGreaterThanEqualRequested less threads

0.75% flaky on one slow device.

Fixes: 362829718
Test: TH

Change-Id: I850edc835d9ff07fc283825a0cbe1a752ba369c5
diff --git a/libs/binder/tests/binderRpcTest.cpp b/libs/binder/tests/binderRpcTest.cpp
index fbca35e..a1e53c5 100644
--- a/libs/binder/tests/binderRpcTest.cpp
+++ b/libs/binder/tests/binderRpcTest.cpp
@@ -454,7 +454,7 @@
         GTEST_SKIP() << "This test requires multiple threads";
     }
 
-    constexpr size_t kNumThreads = 10;
+    constexpr size_t kNumThreads = 5;
 
     auto proc = createRpcTestSocketServerProcess({.numThreads = kNumThreads});