Issue:
fix: Ability to change TOTP issuer name depending on the env

As of now, the issuer name in TOTP is always "Hyperswitch" independent of env.

As TOTP will be present in multiple environments, we need to have different issuer names for all the environments, so that user can easily identify the TOTP.

Resolution:
<think>
PR Context:
- Title: feat(users): Create config for TOTP Issuer
- Merged: 2024-06-03T14:07:38Z
- Files changed: 11 files
- Commits: 8 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [ ] Bugfix
- [ ] New feature
- [x] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->
This PR adds configs for TOTP Issuer (to easily change issuer name of TOTP)

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [x] This PR modifies application configuration/envi
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** feat(users): Create config for TOTP Issuer (#4776)
Files to modify:


**crates/router/src/configs/settings.rs**
  Modify existing code

**crates/router/src/consts/user.rs**
  Modify existing code

**crates/router/src/core/user.rs**
  Modify existing code

**crates/router/src/utils/user/two_factor_auth.rs**
  Modify existing code