Fix skip versions of `indices.put_mapping/20_mix_typeless_typeful.yml`.
The test assumed that it could run against all 6.x indices but it actually
requires 6.2+ since 6.2 is the first version that allowed `_doc` as a type
name
Closes
"PUT mapping with _doc on an index that has types":
- skip:
- version: "all"
- reason: 5.x indices can have types that start with an `_` # AwaitsFix: https://github.com/elastic/elasticsearch/issues/38202
+ version: " - 6.1.99"
+ reason: _doc as a type name was only allowed as of 6.2
- do:
