[Maps] retrieve geo_point value from docvalue_fields instead of _source

[nreese]

fixes #45270

This PR updates the Elasticsearch search request to request geo_point geometry from docvalue_fields instead of _source. This way, docvalue_fields will come back in a lat,lon string format regardless of how the field is stored in _source.

Run the following in console to load a test data set with WKT to test the PR out.

PUT test
{}

PUT test/_mapping
{
  "properties": {
    "location": {
      "type": "geo_point"
    }
  }
}

PUT test/_doc/1
{
    "location": "POINT (-71.34 41.12)"
}

PUT test/_doc/2
{
    "location": ["POINT (-68 41.12)", "POINT (-66 41.12)"]
}

[elasticmachine]

Pinging @elastic/kibana-gis (Team:Geo)

[elasticmachine]

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[thomasneirynck]

tested in chrome and works. nice to get some complexity removed from this.

remove

• https://github.com/elastic/kibana/blob/c2dff771f86fd971a1d1262e69fddc43baca5f4b/x-pack/plugins/translations/translations/ja-JP.json#L5760
• https://github.com/elastic/kibana/blob/c2dff771f86fd971a1d1262e69fddc43baca5f4b/x-pack/plugins/translations/translations/zh-CN.json#L5762

to get i18n working

[elasticmachine]

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