This PR has the following changes
1. Add `AZURE_APP_ID` and `AZURE_APP_SECRET` to installation config
2. Add Microsoft config to `super_admin/features.yml`
3. Replace usage of `ENV.fetch` with `GlobalConfigService.load` for
fetch App ID and Secret
- Added a trait called microsoft_email for the Channel::Email factory.
- Rewrote the logic to make it simple to understand
- Rewrote the specs for readability
- Adds the backend APIs required for Microsoft Email Channels
Co-authored-by: Pranav Raj S <pranav@chatwoot.com>
Co-authored-by: Sojan <sojan@pepalo.com>
