Update frontend to Angular 14

[sinedied]

This is quite a big PR, so I'll try to summarize all the changes made and some limitations:

What has been done

• Updated web app from Angular 9 -> Angular 14, making sure intermediate upgrades were functional
• Changed build process from Webpack 4 to using Angular CLI with some Webpack 5 customizations, in-line with latest JHipster tooling
• Removed deprecated tslint and codelyzer in favor of eslint. Rules haven't all been upgraded as it would need a lot of refactoring from the code (maybe done in a separate PR)
• Migrated from moment to dayjs, which reduced the total bundle size by about ~100kb
• Updated Jest and jest-angular, and migrated to use @angular-builders/jest to run unit tests with Angular CLI
• Updated all needed dependencies, added missing peer dependencies and removed unneeded dependencies

Limitations

• rxjs was not migrated to v7, so it's still v6 mainly because of the ng-jhipster dependency
• ng-jhipster is not maintained anymore (and stuck to Angular v10, though still functional). To remove it as a dependency it would need quite a lot of changes in the code (for a another PR)
• Bootstrap was not migrated to v5, so it's still v4. This currently limits to using ng-bootstrap@11 (for Angular 13). It would need quite a big CSS & JS migration, so it would be for another PR.
• Update to Angular 15 is blocked mainly because of the lack of @angular-builders/custom-webpack support for v15, also some other dependencies are not ready yet.
• Because of ng-jhipster and the lack of bootstrap v5 migration, there are some peerDependencies warnings during yarn install, though the app is working fine.

I tested the app locally with the backend and all the screens successfully, but it may need further testing on a preprod env to make sure it doesn't introduce any regression.

cc @jdubois

[jdubois]

@sinedied can you have a look at the merge conflict?

[sinedied]

Merge conflict resolved ✅

[jdubois]

LGTM, thanks @sinedied !