test: redirect comparison tool output to stdout

Otherwise travis thinks the build has stalled.

Makefile.am

@@ -160,7 +160,7 @@ endif
 if USE_COMPARISON_TOOL
 check-local:
 	$(MKDIR_P) qa/tmp
-	@qa/pull-tester/run-bitcoind-for-test.sh $(JAVA) -jar $(JAVA_COMPARISON_TOOL) qa/tmp/compTool $(COMPARISON_TOOL_REORG_TESTS)
+	@qa/pull-tester/run-bitcoind-for-test.sh $(JAVA) -jar $(JAVA_COMPARISON_TOOL) qa/tmp/compTool $(COMPARISON_TOOL_REORG_TESTS) 2>&1
 endif
 
 EXTRA_DIST = $(top_srcdir)/share/genbuild.sh qa/pull-tester/pull-tester.sh qa/rpc-tests $(DIST_DOCS) $(WINDOWS_PACKAGING) $(OSX_PACKAGING)