added note for known typo

[l-trotta]

The ManagedBy enum has a field, Data stream lifecycle, which should have been written like Data Stream Lifecycle.
This is not correct, but it's already part of the API and there are special cases for it in tests, so this PR adds a comment to notify future contributors of this anomaly.

[cla-checker-service]

💚 CLA has been signed

[github-actions]

Following you can find the validation results for the APIs you have changed.

API	Status	Request	Response
indices.add_block	🟢	2/2	2/2
indices.analyze	🟢	20/20	20/20
indices.clear_cache	🟢	4/4	4/4
indices.clone	🟢	6/6	6/6
indices.close	🟢	42/42	42/42
indices.create_data_stream	🟢	25/25	25/25
indices.create	🔴	673/679	679/679
indices.data_streams_stats	🟢	4/4	4/4
indices.delete_alias	🟢	15/15	15/15
indices.delete_data_lifecycle	⚪	Missing test	Missing test
indices.delete_data_stream	🟢	27/27	27/27
indices.delete_index_template	🟢	1/1	1/1
indices.delete_template	🟢	9/9	9/9
indices.delete	🟢	104/104	104/104
indices.disk_usage	🟢	1/1	1/1
indices.downsample	⚪	Missing test	Missing test
indices.exists_alias	🟢	36/36	36/36
indices.exists_index_template	⚪	Missing test	Missing test
indices.exists_template	🟢	15/15	15/15
indices.exists	🟢	39/39	39/39
indices.explain_data_lifecycle	⚪	Missing test	Missing test
indices.field_usage_stats	🟢	5/5	5/5
indices.flush	🟢	9/9	9/9
indices.forcemerge	🔴	4/4	3/4
indices.get_alias	🔴	80/80	68/80
indices.get_data_lifecycle	⚪	Missing test	Missing test
indices.get_data_stream	🔴	12/12	3/12
indices.get_field_mapping	🔴	15/15	14/15
indices.get_index_template	🔴	16/16	14/16
indices.get_mapping	🟢	74/74	74/74
indices.get_settings	🔴	54/54	50/54
indices.get_template	🟢	30/30	30/30
indices.get	🟢	52/52	52/52
indices.migrate_to_data_stream	⚪	Missing test	Missing test
indices.modify_data_stream	⚪	Missing test	Missing test
indices.open	🟢	17/17	17/17
indices.promote_data_stream	⚪	Missing test	Missing test
indices.put_alias	🟢	54/54	54/54
indices.put_data_lifecycle	⚪	Missing test	Missing test
indices.put_index_template	🔴	36/37	37/37
indices.put_mapping	🔴	70/71	71/71
indices.put_settings	🔴	46/48	48/48
indices.put_template	🔴	39/41	41/41
indices.recovery	🟢	11/11	11/11
indices.refresh	🟢	202/202	202/202
indices.reload_search_analyzers	🟢	2/2	2/2
indices.resolve_index	🟢	5/5	5/5
indices.rollover	🟢	14/14	14/14
indices.segments	🔴	6/6	5/6
indices.shard_stores	🔴	5/5	4/5
indices.shrink	🟢	5/5	5/5
indices.simulate_index_template	🟢	4/4	4/4
indices.simulate_template	🟢	4/4	4/4
indices.split	🟢	4/4	4/4
indices.stats	🟢	82/82	81/81
indices.unfreeze	🟢	1/1	1/1
indices.update_aliases	🟢	22/22	22/22
indices.validate_query	🟢	7/7	7/7

You can validate these APIs yourself by using the make validate target.

[swallez]

LGTM. Thanks!