remove build folder and start from scratch

.gitlab-ci.yml

@@ -13,6 +13,7 @@ build:
     script:
         - git submodule sync
         - git submodule update --init --recursive
+        - rm -rf build
         - mkdir -p build
         - cd build
         - qmake ../DRAMSys/DRAMSys.pro
@@ -22,4 +23,4 @@ example_ddr3:
     stage: simple-runs
     script:
         - cd build/simulator
-        - ./DRAMSys
+        - ./DRAMSys