feat: Add support for management endpoint

[skyscrapr]

Problem

Add support for mgmt endpoint:
New resources:

• api_key
• project

New datasources:

• api_key
• api_keys
• project
• projects

Solution

The mgmt endpoint requires a separate client and api key. Therefore two clients are now used by the provider. Each client is configured by a different environment variable to set the respective api_key.

Type of Change

• 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 not work as expected)
• This change requires a documentation update
• Infrastructure change (CI configs, etc)
• Non-code change (docs, etc)
• None of the above: (explain here)

Test Plan

Test output: TBD. This will require the MGMT api key to be added tot he repo secrets.