surfaceflinger_fuzzer : Resolved memory leak

Test: ./surfaceflinger_fuzzer
Bug: 251848241

Change-Id: I7a470f276b5886f86b80faa1827249c4265aa0fe
(cherry picked from commit cbcf790edab2306e4b55e441111592ff5e77c611)
diff --git a/services/surfaceflinger/fuzzer/surfaceflinger_fuzzer.cpp b/services/surfaceflinger/fuzzer/surfaceflinger_fuzzer.cpp
index 22d80ca..a3da4dc 100644
--- a/services/surfaceflinger/fuzzer/surfaceflinger_fuzzer.cpp
+++ b/services/surfaceflinger/fuzzer/surfaceflinger_fuzzer.cpp
@@ -245,6 +245,7 @@
     setDisplayStateLocked();
 
     setTransactionState();
+    mTestableFlinger.flushTransactionQueues();
 
     onTransact(data, size);
 }