Revalidate the IPstack API documentation to use the latest authentication attributes

[Subhajit97]

Is your feature request related to a problem? Please describe.
N/A

Describe the solution you'd like
The IPstack plugin currently utilizes an outdated Go SDK, which has some mismatch in the authentication attributes with the latest IPstack API authentication methods as outlined in the official IPstack API documentation.

Describe alternatives you've considered

• Review the latest IPstack API documentation.
• Identify changes required in the plugin's codebase to accommodate the new authentication method.
• Test the updated plugin against the current IPstack API to ensure functionality.

Additional context
Add any other context or screenshots about the feature request here.