Add supporting study method types slot to association class

[kevinschaper]

Summary

The supporting study method types slot is defined in the schema and inherits from supporting study metadata → association slot (which has domain: association), but it is not explicitly declared in the association class's slots list. It should be added so that any association can explicitly declare supporting study method types.

Current State

• supporting study method types is defined as a slot with:
  • is_a: supporting study metadata
  • range: uriorcurie
  • multivalued: true
• Its parent association slot has domain: association, but the slot is not listed in the association class's slots directly.

Proposed Change

Add supporting study method types to the association class's slots list in biolink-model.yaml, ensuring it is explicitly available on any association edge.