[PS-1531]Sentence case browser

[danielleflinn]

Type of change

Copy updated. Transition web vault strings to use sentence case for all UI elements, except the following terms:

• Branded Names: Provider(s) + Provider Portal, Send(s) + Send, Directory Connector • Plan Names: Premium, Families, Teams, Enterprise

- [ ] Bug fix
- [ ] New feature development
- [ ] Tech debt (refactoring, code cleanup, dependency upgrades, etc)
- [ ] Build/deploy pipeline (DevOps)
- [X] Other

Objective

Currently the use of Title and Sentence case is inconsistent throughout the product. To improve the UI consistency, readability, and localization, this change updates strings to use sentence case.

Code changes

_locales/en/messages.json

Before you submit

• Please add unit tests where it makes sense to do so (encouraged but not required)
• If this change requires a documentation update - notify the documentation team
• If this change has particular deployment requirements - notify the DevOps team