Alternative implementation of databricks_permission resource for managing permissions for individual principals.

[alexott]

Changes

This resource provides fine-grained control over permissions by managing a single principal's access to a single object, unlike databricks_permissions, which manages all principals' access to an object at once. This is particularly useful for:

• Managing permissions for different teams independently
• Token and password authorization permissions that previously required all principals in one resource
• Avoiding conflicts when multiple configurations manage different principals on the same object

Caveat: Since we cannot remove an individual permission, the Delete operation is performed as Read/Put, so we need to use a lock around each object.

Tests

• make test run locally
• relevant change in docs/ folder
• covered with integration tests in internal/acceptance
• using Go SDK
• using TF Plugin Framework
• has entry in NEXT_CHANGELOG.md file