refactor: Remove batch concept from opendal #2129

Job	Run time
check_msrv	32s
check_clippy	4m 5s
build_all_features	4m 48s
build_all_platforms (ubuntu-latest)	2m 34s
build_under_wasm	46s
build_default_features (ubuntu-latest)	33s
build_all_platforms (macos-latest)	2m 30s
build_default_features (macos-latest)	39s
build_all_platforms (windows-latest)	5m 51s
check_docs	3m 23s
build_default_features (windows-latest)	1m 58s
unit	6m 13s
	33m 52s

Provide feedback