chore: add dependabot to the repository (#83)

## Description
A lot of dependencies are outdated, this adds dependabot to ensure that dependencies stay updated.

## Changes
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- Detail the changes you have introduced.
- Highlight any new functionality.
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## Fixes <!-- #issueNumber -->

## Checklist
- [x] I have read the **CONTRIBUTING.md** document.
- [x] My code follows the code style of this project.
- [x] I have added tests to cover my changes.
- [x] All new and existing tests passed.
- [x] I have updated the documentation accordingly.
- [x] This change requires a change to the documentation on the website.

## Additional Information
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---------

Signed-off-by: Manuel Rüger <manuel@rueg.eu>
Co-authored-by: ccoVeille <3875889+ccoVeille@users.noreply.github.com>

.github/dependabot.yml

@@ -0,0 +1,12 @@
+version: 2
+updates:
+  - package-ecosystem: "gomod"
+    directory: "/"
+    open-pull-requests-limit: 10  # avoid spam, if no one reacts
+    schedule:
+      interval: "weekly"
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    open-pull-requests-limit: 10  # avoid spam, if no one reacts
+    schedule:
+      interval: "weekly"