This trial patch set moves compaction_strategy.hh and compaction_garbage_collector.hh to compaction directory and drops two unused compact_for_mutation_query_state and compact_for_data_query_state.
Closes#9156
* github.com:scylladb/scylla:
compaction: Move compaction_garbage_collector.hh to compaction dir
compaction: Move compaction_strategy.hh to compaction dir
mutation_compactor: Drop compact_for_mutation_query_state and compact_for_data_query_state