Fix handling of circles in legacy geo_shape queries

[imotov]

Brings back support for circles in legacy geo_shape queries that
was accidentally lost during query refactoring.

Fixes #49296

[elasticmachine]

Pinging @elastic/es-analytics-geo (:Analytics/Geo)

[iverase]

Is there a test that checks we still throw a meaningful error for the BKD case?

[imotov]

@elasticmachine run elasticsearch-ci/1
@elasticmachine run elasticsearch-ci/2

[imotov]

Is there a test that checks we still throw a meaningful error for the BKD case?

We have a unit test for that.

The error changed a bit, since we detect the issue a bit later when we actually have mapper at hands, but it is still meaningful:

{
  "error": {
    "root_cause": [
      {
        "type": "mapper_parsing_exception",
        "reason": "failed to parse field [location] of type [geo_shape]"
      }
    ],
    "type": "mapper_parsing_exception",
    "reason": "failed to parse field [location] of type [geo_shape]",
    "caused_by": {
      "type": "unsupported_operation_exception",
      "reason": "CIRCLE geometry is not supported"
    }
  },
  "status": 400
}

[iverase]

LGTM