Bump oxsecurity/megalinter from 6 to 7 (#19)

Bumps [oxsecurity/megalinter](https://github.com/oxsecurity/megalinter) from 6 to 7.
- [Release notes](https://github.com/oxsecurity/megalinter/releases)
- [Changelog](https://github.com/oxsecurity/megalinter/blob/main/CHANGELOG.md)
- [Commits](oxsecurity/megalinter@v6...v7)

---
updated-dependencies:
- dependency-name: oxsecurity/megalinter
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/mega-linter.yml

@@ -30,7 +30,7 @@ jobs:
         id: ml
         # You can override MegaLinter flavor used to have faster performances
         # More info at https://megalinter.io/flavors/
-        uses: oxsecurity/megalinter/flavors/dotnet@v6
+        uses: oxsecurity/megalinter/flavors/dotnet@v7
         env:
           # All available variables are described in documentation
           # https://megalinter.io/configuration/