SONAR-13940 Add missing translation key for zero GitLab instances

sonar-core/src/main/resources/org/sonar/l10n/core.properties

@@ -3223,6 +3223,7 @@ onboarding.create_project.too_many_alm_instances.github=You must have exactly 1
 onboarding.create_project.alm_instances_count_X=You currently have {0}.
 onboarding.create_project.zero_alm_instances.bitbucket=You must first configure a Bitbucket Server instance.
 onboarding.create_project.zero_alm_instances.github=You must first configure a GitHub instance.
+onboarding.create_project.zero_alm_instances.gitlab=You must first configure a GitLab instance.
 onboarding.create_project.wrong_binding_count=You must have exactly 1 {alm} instance configured in order to use this method, but none were found. Either create the project manually, or contact your system administrator.
 onboarding.create_project.wrong_binding_count.admin=You must have exactly 1 {alm} instance configured in order to use this method. You can configure instances under {url}.
 onboarding.create_project.enter_pat=Enter personal access token