add missing redirects for "get started" page (#23300)

- fixes #23295

Also moved one redirect to a more suitable page.

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## Description

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## Related issues or tickets

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Signed-off-by: Sebastiaan van Stijn <[email protected]>

Author: thaJeztah

content/get-started/_index.md

@@ -29,8 +29,8 @@ params:
     link: /get-started/workshop/
     icon: desk
 aliases:
+  - /engine/get-started/
   - /engine/tutorials/usingdocker/
-  - /get-started/what-is-a-container/
 ---
 
 If you're new to Docker, this section guides you through the essential resources to get started.

content/get-started/docker-concepts/the-basics/what-is-a-container.md

@@ -8,6 +8,7 @@ aliases:
 - /guides/walkthroughs/run-a-container/
 - /guides/walkthroughs/
 - /get-started/run-your-own-container/
+- /get-started/what-is-a-container/
 - /guides/docker-concepts/the-basics/what-is-a-container/
 ---