ci: add libldap2-dev to requirements

.gitlab-ci.yml

@@ -14,7 +14,7 @@ stages:
 
 .install_requirements: &install_requirements
   - apt-get -qq update
-  - apt-get -y install curl pip
+  - apt-get -y install curl pip libldap2-dev
   - python3 -m pip install --upgrade pip
   - pip install poetry
   - poetry install --no-interaction