no error if folder exists

.gitlab-ci.yml

@@ -12,7 +12,7 @@ cmake:
   stage: cmake
   image: conanio/gcc9:latest
   script:
-    - mkdir build
+    - mkdir build -p
     - cd build
     - conan remote add bintray https://api.bintray.com/conan/lheili/LibConfig
     - conan user lukas-heiligenbrunner -r bintray -p $CONAN_KEY