CI: Try to build examples in second time in case of error

It will help to work around the weird bug during buillding a batch of examples

.gitlab-ci.yml

@@ -154,6 +154,7 @@ build_esp_idf_tests:
 
 .build_examples_template: &build_examples_template
   <<: *build_template
+  retry: 1
   artifacts:
     when: always
     paths: