fix(renovate): Flux Config add Helm Repo

[Boemeltrein]

Description

The Helm Releases are now detected, but cannot define versions as the repo is unknown.
Example Log without adding this change "skipReason": "unknown-registry",:

  {
        "deps": [
          {
            "currentValue": "19.5.23",
            "datasource": "helm",
            "depName": "blocky",
            "packageName": "blocky",
            "skipReason": "unknown-registry",
            "updates": []
          }
        ],
        "packageFile": "clusters/main/kubernetes/core/blocky/app/helm-release.yaml"
      },

This PR will resolve this.

⚒️ Fixes #

⚙️ Type of change

• ⚙️ Feature/App addition
• 🪛 Bugfix
• ⚠️ Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 🔃 Refactor of current code
• 📜 Documentation Changes

🧪 How Has This Been Tested?

Add own TestCluster..

📃 Notes:

✔️ Checklist:

• ⚖️ My code follows the style guidelines of this project
• 👀 I have performed a self-review of my own code
• #️⃣ I have commented my code, particularly in hard-to-understand areas
• 📄 I have made changes to the documentation
• 🧪 I have added tests to this description that prove my fix is effective or that my feature works
• ⬆️ I increased versions for any altered app according to semantic versioning
• I made sure the title starts with feat(chart-name):, fix(chart-name):, chore(chart-name):, docs(chart-name): or fix(docs):

➕ App addition

If this PR is an app addition please make sure you have done the following.

• 🖼️ I have added an icon in the Chart's root directory called icon.png

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