Issue:
fix: revert mget use authorization

In the hosted environment, where we have multiple redis clusters `mget` is not working as expected and throwing the following error: `Unknown Error: CROSSSLOT Keys in request don't hash to the same slot`.

Temporary fix is to revert the PR which is using `mget`

Resolution:
<think>
PR Context:
- Title: fix(users): revert using mget in authorization
- Merged: 2024-03-07T08:22:10Z
- Files changed: 1 files
- Commits: 1 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [x] Bugfix
- [ ] New feature
- [ ] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
`mget` is not working in the hosted version. So, this PR will revert the #3945 which uses `mget``.

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** fix(users): revert using mget in authorization (#3999)
Files to modify:


**crates/router/src/services/authentication/blacklist.rs**
  Modify existing code