[SG-823] Undid changes to capture device push token on login

[trmartin4]

Type of change

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

Objective

In #2404 and #2420, I introduced a change that moved the SaveAsync() for devices so that it saves the device on every login, not just the initial login for that device. The intent was to allow the push token to be sent on the login request and updated at that time.

In the meantime, I have discovered another way to solve this problem more directly and efficiently in the Bitwarden mobile codebase. These changes are included in this mobile PR. Doing these changes will make saving the push token on login redundant and add in a database call on every login for no reason.

This PR reverts those changes in BaseRequestValidator.

Code changes

• BaseRequestValidator.cs: Undid the changes that were in Update push token on login to allow multiple users on mobile devices #2404.

Before you submit

• Please check for formatting errors (dotnet format --verify-no-changes) (required)
• If making database changes - make sure you also update Entity Framework queries and/or migrations
• 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

[differsthecat]

This looks good. The only difference I see is that you kept the test changes you did in the previous PR intentionally 👍