[Standardization] Refactor Providers

[TanmoySG]

Currently there are four Providers in use

• loginProvider
• registrationProvider
• mailer
• authlib

The naming for the four components are not unified as two of them (loginProvider and registrationProvider) use "Provider" along with the component name and other two dont. The task is to unify the naming by refactoring the code.

[Checkpoints]

• [x] Change loginProvider ➡️ login
• [x] Change registrationProvider ➡️ registration
• [x] Refactor dependant code across scripts
• [x] Test Changes

[TanmoySG]

Commits related to the Refactoring

• https://github.com/TanmoySG/wunder-identity-provider/commit/a4a5e51270a2c9cc5403f7f5f0debba4ec46fa46
• https://github.com/TanmoySG/wunder-identity-provider/commit/5ebcc61c8a4d58b4457a0cef649b17bd816dee7c
• https://github.com/TanmoySG/wunder-identity-provider/commit/592672ace739f7c0677ea0c33f43af26b5d2e909
• https://github.com/TanmoySG/wunder-identity-provider/commit/0ff58e76e1b4c044ffb776d2c3c4406273396a78

[TanmoySG]

Tested ⚙️ 🛠

Working ✅