Check directory existence again when failing to create it to avoid erroring out on race condition

integration_tests/threaded_test.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+
+. ./test_functions.sh
+
+fixture
+
+pushd ${TEST_REPO}
+${DUPLICACY} init integration-tests $TEST_STORAGE -c 1k
+
+add_file file3
+add_file file4
+
+
+${DUPLICACY} backup -threads 16 
+${DUPLICACY} check --files -stats
+popd