.gitlab-ci.yml: Fix package installation

.gitlab-ci.yml

 image: debian:testing-slim
 
-before_script:
-  - apt-get update && apt-get install -y libhts3 zlib1g libsdsl3
-
 build:
   stage: build
   before_script:
-    - apt-get update && apt-get install -y make g++ libsdsl-dev libhts-dev zlib1g-dev
+    - apt-get update && apt-get install -y make g++ libhts3 zlib1g libsdsl3 libsdsl-dev libhts-dev zlib1g-dev
   script:
     - make
     - make -C tests
@@ -19,7 +16,7 @@ build:
 test:
   stage: test
   before_script:
-    - apt-get update && apt-get install -y zutils diffutils
+    - apt-get update && apt-get install -y libhts3 zlib1g libsdsl3 zutils diffutils
   script:
     - cd tests
     - ./test_bam