test: cleanup temporary file for TestConfigFromFile

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>

client/v3/yaml/config_test.go

@@ -98,6 +98,7 @@ func TestConfigFromFile(t *testing.T) {
 			continue
 		}
 		if cerr != nil {
+			os.Remove(tmpfile.Name())
 			continue
 		}