[BUG] extra free-format object in match all query

[amberzsy]

What is the bug?

opensearch-api-specification/spec/schemas/_common.query_dsl.yaml

Line 986 in 508c210

MatchAllQuery:

extra free-format object in match all query, which is not correct. public doc

    MatchAllQuery:
      allOf:
        - $ref: '#/components/schemas/QueryBase'
        - type: object

in json format would be

{
     "match_all": {}
}
[supported] or 
{
     "match_all": {
               "boost": 1.2,
                "_name": "xyz"
     }
}
[supported] or 
{
     "match_all": {
               "boost": 1.2,
                "_name": "xyz"
     }, 
     "any_key": {}
}
[not supported]

How can one reproduce the bug?

N/A

What is the expected behavior?

N/A

[dblock]

Closed via #572