Bump angular from 1.7.2 to 1.8.3 in /public/libs/angularjs-toast

Bumps [angular](https://github.com/angular/angular.js) from 1.7.2 to 1.8.3.
- [Release notes](https://github.com/angular/angular.js/releases)
- [Changelog](https://github.com/angular/angular.js/blob/master/CHANGELOG.md)
- [Commits](angular/angular.js@v1.7.2...v1.8.3)

---
updated-dependencies:
- dependency-name: angular
  dependency-type: direct:development
...

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Author: dependabot[bot]