Correctly resolve type for delete operations

[romseygeek]

#62616 refactored how we deal with building mapping updates for
delete operations against an empty index. In 7x, delete operations
include a type as part of the operation UID, and this type needs to
be resolved against mappings. In particular, the type _doc can
mean either a type called _doc (the general case), or it can mean
whatever type this index actually has. There are two code paths
in IndexShard.applyDeleteOperation, one for empty mappings
and one for the standard case; #62616 was resolving the type for
the first code path, but not the second, which meant that some
delete operations could be written to the translog with an incorrect
type.

This commit adds type resolution to the second code path as well.

Fixes #72735

[elasticmachine]

Pinging @elastic/es-search (Team:Search)

[elasticmachine]

Pinging @elastic/es-distributed (Team:Distributed)

[romseygeek]

Marked as >non-issue because this is an unreleased bug.

I'm not very satisfied with just adding an assert as a test here, but the buggy method doesn't actually contain the relevant information as part of its return type and I am unsure of how to add checks on the method's side effects - if anyone has any clever ideas then let me know.

[dnhatn]

LGTM.

[dnhatn]

I'm not very satisfied with just adding an assert as a test here, but the buggy method doesn't actually contain the relevant information as part of its return type and I am unsure of how to add checks on the method's side effects - if anyone has any clever ideas then let me know.

I will try to add a test for this. I think it's ok to merge this now to stabilize CI.

[romseygeek]

I will try to add a test for this. I think it's ok to merge this now to stabilize CI.

Thanks @dnhatn!