Remove supportsReadConcernMajority from StorageEngine interface and all its inherited classes.

Where we use storageEngine->supportsReadConcernMajority:

• BackupCursorService::extendBackupCursor()
• Keys_collection_cache_test.cpp
• Keys_collection_manager_sharding_test.cpp
• _initAndListen in mongod_main.cpp
• Vector_clock_mongod_test.cpp
• initializeGlobalShardingStateForMongoD in sharding_initialization_mongod.cpp
• Vector_clock_shard_server_test.cpp
• Storage_engine_impl.cpp
• We may also want to remove supportsResumableIndexBuilds() and supportsPendingDrops() which are same as supportsReadConcernMajority()
• IndexBuildsCoordinator::isIndexBuildResumeable
• StorageEngineImpl::_handleInternalIdent and _dropCollection
• Database_impl.cpp
• Rollback_impl.cpp
• Storage_timestamp_test.cpp
• Storage_init.cpp
• storage_util.cpp