install pytest (#56206)

roles/base/tasks/main.yml

@@ -76,6 +76,11 @@
     name: psycopg2-binary
     virtualenv: "{{venv_py3}}"
 
+- name: install pytest
+  pip:
+    name: pytest
+    virtualenv: "{{venv_py3}}"
+
 - name: "create {{src_dir}} directory"
   file:
     path: "{{src_dir}}"