makefile: fix rebuild IT binary condition

Currently, we rebuild (even if it exists) IT binary
if DONT_REBUILD_INTEGRATION_BIN env var is non-empty.
I believe it should be the opposite.

Author: muzarski

Makefile

@@ -172,18 +172,18 @@ download-ccm-cassandra-image: install-ccm-if-missing
 
 run-test-integration-scylla: prepare-integration-test download-ccm-scylla-image
 ifeq ($(DONT_REBUILD_INTEGRATION_BIN), $(EMPTY))
-run-test-integration-scylla: build-integration-test-bin-if-missing
-else
 run-test-integration-scylla: build-integration-test-bin
+else
+run-test-integration-scylla: build-integration-test-bin-if-missing
 endif
 	@echo "Running integration tests on scylla ${SCYLLA_VERSION}"
 	valgrind --error-exitcode=123 --leak-check=full --errors-for-leak-kinds=definite build/cassandra-integration-tests --scylla --version=${SCYLLA_VERSION} --category=CASSANDRA --verbose=ccm --gtest_filter="${SCYLLA_TEST_FILTER}"
 
 run-test-integration-cassandra: prepare-integration-test download-ccm-cassandra-image install-java8-if-missing
 ifeq ($(DONT_REBUILD_INTEGRATION_BIN), $(EMPTY))
-run-test-integration-cassandra: build-integration-test-bin-if-missing
-else
 run-test-integration-cassandra: build-integration-test-bin
+else
+run-test-integration-cassandra: build-integration-test-bin-if-missing
 endif
 	@echo "Running integration tests on cassandra ${CASSANDRA_VERSION}"
 	valgrind --error-exitcode=123 --leak-check=full --errors-for-leak-kinds=definite build/cassandra-integration-tests --version=${CASSANDRA_VERSION} --category=CASSANDRA --verbose=ccm --gtest_filter="${CASSANDRA_TEST_FILTER}"