build: (deps): bump matrix from 6.2.0 to 7.0.0

Bumps [matrix](https://github.com/famedly/matrix-dart-sdk) from 6.2.0 to 7.0.0.
- [Release notes](https://github.com/famedly/matrix-dart-sdk/releases)
- [Changelog](https://github.com/famedly/matrix-dart-sdk/blob/main/CHANGELOG.md)
- [Commits](https://github.com/famedly/matrix-dart-sdk/compare/v6.2.0...v7.0.0)

---
updated-dependencies:
- dependency-name: matrix
  dependency-version: 7.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

pubspec.yaml

@@ -49,7 +49,7 @@ dependencies:
   intl: any
   just_audio: ^0.10.5
   latlong2: ^0.9.1
-  matrix: ^6.2.0
+  matrix: ^7.0.0
   mime: ^2.0.0
   native_imaging: ^0.4.0
   opus_caf_converter_dart: ^1.0.1