i18n(de): translate guides/upgrade-to/v5.mdx

[trueberryless]

Description (required)

• translate guides/upgrade-to/v5.mdx

• waiting for other pages cause of links:

  guides/imports
  guides/routing
  reference/adapter-reference
  reference/integrations-reference

Related issues & labels (optional)

• 5.0.0 beta docs #9240
• Suggested label: i18n

[netlify]

✅ Deploy Preview for astro-docs-2 ready!

Built without sensitive environment variables

Name	Link
🔨 Latest commit	c53950e
🔍 Latest deploy log	https://app.netlify.com/sites/astro-docs-2/deploys/676314b4b9c6100008cd8290
😎 Deploy Preview	https://deploy-preview-10302--astro-docs-2.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[astrobot-houston]

Lunaria Status Overview

🌕 This pull request will trigger status changes.

Learn more

By default, every PR changing files present in the Lunaria configuration's files property will be considered and trigger status changes accordingly.

You can change this by adding one of the keywords present in the ignoreKeywords property in your Lunaria configuration file in the PR's title (ignoring all files) or by including a tracker directive in the merged commit's description.

Tracked Files

File	Note
de/guides/upgrade-to/v5.mdx	Localization added, will be marked as complete.

Warnings reference

Icon	Description
🔄️	The source for this localization has been updated since the creation of this pull request, make sure all changes in the source have been applied.