Merge pull request #911 from issyl0/docs_fix_formatting

Basic Project docs: Add blank lines before code blocks to fix formatting

Author: k8s-ci-robot

docs/book/src/cronjob-tutorial/basic-project.md

@@ -15,12 +15,14 @@ First up, basic infrastructure for building your project:
 </details>
 
 <details><summary>`Makefile`: Make targets for building and deploying your controller</summary>
+
 ```makefile
 {{#include ./testdata/project/Makefile}}
 ```
 </details>
 
 <details><summary>`PROJECT`: Kubebuilder metadata for scaffolding new components</summary>
+
 ```yaml
 {{#include ./testdata/project/PROJECT}}
 ```