Issue:
Todo redis interface

## Type of Change
<!-- Put an `x` in the boxes that apply -->
- [x] Enhancement

## Description
This PR is a part of greater refactoring which aims on removing `// TODO: ...` & `// FIXME: ..` from the entire codebase.
The objective of this PR is to fix `xgroup_create` by adding a guard or some specific `RedisEntryId` while also adding unit tests for the same. It also adds crate documentation for the `redis_interface` crate
<!-- Describe your changes in detail -->


### Additional Changes

- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

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1. `config`
2. `crates/router/src/configs`
3. `loadtest/config`
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## Motivation and Context
The codebase wide initiative in fixing existing problems, `TODO:`s and `FIXME:`s while also adding documentations.
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## How did you test it?
unit-tests included
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## Checklist
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- [x] I formatted the code `cargo +nightly fmt`
- [x] I addressed lints thrown by `cargo clippy`
- [x] I reviewed submitted code
- [x] I added unit tests for my changes where possible

Resolution:
<think>
PR Context:
- Title: fix: fix email verification regex & unittests
- Merged: 2022-12-13T16:09:25Z
- Files changed: 1 files
- Commits: 1 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [x] Enhancement

## Description
The PR focuses on removing `TODO: ..` from `common_utils` and is part of the chain of PR's i.e.
1. #136 
<!-- Describe your changes in detail -->


### Additional Changes

- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

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Provide links to the files with corresponding changes.

Following are the paths where you c
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** fix: fix email verification regex & unittests (#139)
Files to modify:


**crates/common_utils/src/validation.rs**
  Add:
    - function: private::proptest_invalid_email