fix bug in GenericRequest.to_dict()

[khancode]

High Level Overview of Change

Fix bug in GenericRequest.to_dict()

Context of Change

There's an initialization bug in GenericRequest where command param doesn't get set to method:

>>> GenericRequest(command='validator_list_sites').to_dict()
{'method': 'zzgeneric_request', 'command': 'validator_list_sites'}

Correct state:

>>> GenericRequest(command='validator_list_sites').to_dict()
{'method': 'validator_list_sites'}

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)
• Refactor (non-breaking change that only restructures code)
• Tests (You added tests for code that already exists, or your new feature included in this PR)
• Documentation Updates
• Release

Test Plan

Added unit test to check GenericRequest state after initialization.

[mvadari]

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