Delete old circleci config

cli/.circleci/config.yml

@@ -1,38 +0,0 @@
-version: 2
-workflows:
-  version: 2
-  test:
-    jobs:
-      - test-3.6
-      - test-3.7
-      - test-3.8
-
-jobs:
-  test-3.6: &test-template
-    docker:
-      - image: circleci/python:3.6-buster
-
-    working_directory: ~/repo
-
-    steps:
-      - checkout
-
-      - run:
-          name: Install dependencies
-          command: |
-            poetry install
-
-      - run:
-          name: Run unit tests
-          command: |
-            poetry run pytest -vvv ./tests
-
-  test-3.7:
-    <<: *test-template
-    docker:
-      - image: circleci/python:3.7-buster
-
-  test-3.8:
-    <<: *test-template
-    docker:
-      - image: circleci/python:3.8-buster