test: remove unused import from feature_masternode_params

Remove unused assert_equal import to fix linter warning.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: PastaPastaPasta

test/functional/feature_masternode_params.py

@@ -9,7 +9,6 @@
 """
 
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal
 
 # Service flags
 NODE_COMPACT_FILTERS = (1 << 6)