Fix CI build

.gitlab-ci.yml

@@ -5,7 +5,7 @@ image: gcc
 build:
   stage: build
   before_script:
-    - apt update && apt -y install cmake make libsdl2-dev gcovr
+    - apt update && apt -y install cmake make libsdl2-dev libsdl2-ttf-dev
   script:
     - mkdir build && cd build
     - cmake ..