Bump intl from 0.19.0 to 0.20.0 (#36)

Bumps [intl](https://github.com/dart-lang/i18n/tree/main/pkgs) from 0.19.0 to 0.20.0.
- [Release notes](https://github.com/dart-lang/i18n/releases)
- [Commits](https://github.com/dart-lang/i18n/commits/intl-v0.20.0/pkgs)

---
updated-dependencies:
- dependency-name: intl
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

pubspec.yaml

@@ -16,7 +16,7 @@ dependencies:
   json_annotation: ^4.8.1
 
 dev_dependencies:
-  intl: ">=0.18.1 <0.20.0"
+  intl: ">=0.18.1 <0.21.0"
   test: ^1.17.10
   mockito: ^5.0.15
   build_runner: ^2.1.1