diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 9b4aa710050da8594c3f4d0bd42ccd68c5e6243f..5c6467894a12b8dcc96010f4eb516149a86b6b8a 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,7 +1,7 @@
 variables:
-  GIT_STRATEGY: none
-  GIT_SUBMODULE_STRATEGY: none
-  GIT_CHECKOUT: false
+  GIT_STRATEGY: "none"
+  GIT_SUBMODULE_STRATEGY: "none"
+  GIT_CHECKOUT: "false"
 
 before_script:
  - |