Adds a "local" storage driver that handles all operations in memory

[lonelycode]

Description

This PR adds a "local" storage handler type, this uses an in-memory non-blocking hashmap to store data, the implementation is entirely in Go, and the local handler API object is designed to take any KV store as a back-end but will perform all advanced operations (such as sets and sorted sets) in go instead of using native capabilities. This is so we can experiment with multiple k/v stores without having to write a whole new interface implementation from scratch (e.g. some k/v stores may not have delete or flush capabilities).

Related Issue

https://tyktech.atlassian.net/browse/TT-748

Motivation and Context

Having a "stateless" version of Tyk makes testing easier for end users and our team. It also means that new users can"kick the tyres" quickly without needing to set up Redis and therefore get time-to-value down.

Test Coverage For This Change

Changes were tested with the existing testutil package, extended for all temporal components including a queue mock, also added one additional test to ensure that the Increment() feature actually incremented.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Refactoring or add test (improvements in base code or adds test coverage to functionality)
• Documentation updates or improvements.

Checklist

• I have reviewed the guidelines for contributing to this repository.
• Make sure you are requesting to pull a topic/feature/bugfix branch (right side). If PRing from your fork, don't come from your master!
• Make sure you are making a pull request against our master branch (left side). Also, it would be best if you started your change off our latest master.
• My change requires a change to the documentation.
  • I have manually updated the README(s)/documentation accordingly.
  • If you've changed APIs, describe what needs to be updated in the documentation.
• I have updated the documentation accordingly.
• Modules and vendor dependencies have been updated; run go mod tidy && go mod vendor
• When updating library version must provide reason/explanation for this update.
• I have added tests to cover my changes.
• All new and existing tests passed.
• Check your code additions will not fail linting checks:
  • gofmt -s -w .
  • go vet ./...

[github-actions]

CLA Assistant Lite bot All contributors have signed the CLA ✍️ ✅

[lonelycode]

I have read the CLA Document and I hereby sign the CLA

[sonarqubecloud]

Quality Gate failed

Failed conditions
C Reliability Rating on New Code (required ≥ A)

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