Circle CI: run tests in sequence

.circleci/config.yml

@@ -73,30 +73,38 @@ jobs:
           command: ./ci_build.sh
 
 workflows:
-  tests-containers:
+  version: 2
+  tests:
     jobs:
+      - install-python-and-test-ubuntu:
+          matrix:
+            parameters:
+              python-version: ["3.8"]
+      - install-python-and-test-ubuntu:
+          requires:
+            - install-python-and-test-ubuntu-3.8
+          matrix:
+            alias: install-python-and-test-ubuntu-all
+            parameters:
+              python-version: ["2.7", "3.5", "3.6", "3.7", "3.9", "3.10", "3.11"]
       - test:
+          requires:
+            - install-python-and-test-ubuntu-all
           matrix:
+            alias: test-containers
             parameters:
               python-version: ["2.7", "3.5", "3.6", "3.7", "3.8", "3.9", "3.10", "3.11"]
               build-type: ["centos_containers", "debian_containers"]
-  tests-sys-debian:
-    jobs:
       - test:
+          requires:
+            - test-containers
           matrix:
             parameters:
               python-version: ["3.9"]
               build-type: ["debian_sys_container"]
-  tests-ubuntu-machines:
-    jobs:
-      - install-python-and-test-ubuntu:
-          matrix:
-            parameters:
-              python-version: ["2.7", "3.5", "3.6", "3.7", "3.8", "3.9", "3.10", "3.11"]
-  tests-macos-machines:
-    jobs:
       - install-python-and-test-macos:
+          requires:
+            - install-python-and-test-ubuntu-all
           matrix:
             parameters:
               python-version: ["3.7", "3.8", "3.9"]
-