limit concurrency of jobs

.gitlab-ci.yml

@@ -16,6 +16,7 @@ stages:
 
 .build_template_linux_64:
   extends: .build_template
+  resource_group: linux_64
   after_script:
     - chmod -R a+w build_artifacts
   tags:
@@ -23,6 +24,7 @@ stages:
 
 .build_template_build_osx_64:
   extends: .build_template
+  resource_group: osx_64
   before_script:
     - unset CI
   tags:
@@ -31,6 +33,7 @@ stages:
 
 .build_template_osx_arm64:
   extends: .build_template
+  resource_group: osx_arm64
   before_script:
     - unset CI
   tags: