Fix: remove "examples" from application > Docker

[judu]

Checking for existing issue

• [X] I have checked for existing issues

Describe the content you'd like to see

The "Configure your Docker application" section in https://developers.clever-cloud.com/doc/applications/docker/ contains a few sections that don't belong there:

• https://developers.clever-cloud.com/doc/applications/docker/#dockerized-rust-application-deployment
• https://developers.clever-cloud.com/doc/applications/docker/#dockerized-hhvm-application-deployment
• https://developers.clever-cloud.com/doc/applications/docker/#sample-dockerized-applications

We should have a L2 section "Samples and tutorials", put the list of sample applications there, and link to proper guides for the first two sections that don't belong there.

It will unclutter the Docker page.

[judu]

(Don't hesitate to assign me or @Dekabry on that)