Fix moved default storage dir outside the nethermind repo folder but authentication error in JSON-RPC request

[Dhir0808]

Fix authentication error in JSON-RPC request

Fixes #7795

Changes

• Updated the JSON-RPC request to include the correct authentication headers based on the XDG environment variables.
• Implemented error handling to manage authentication failures gracefully.
• Note: Unit tests for the new authentication logic have not yet been written.

Types of changes

• Bugfix (a non-breaking change that fixes an issue)

Testing

Requires testing

• Yes

If yes, did you write tests?

• Yes
• No

Notes on testing

• Unit tests for verifying authentication error handling and header correctness are planned but not yet implemented.

Documentation

Requires documentation update

• Yes
• No

Requires explanation in Release Notes

• Yes
• No

[rubo]

I'm not sure about this. Commented on the issue.

[obasekiosa]

@Dhir0808
you can modify this (change title and revert old commits and force push new commits) to simply to match the new direction.
no need for a new pr.