[DOC]Enhance Logstash geo_shape field example

[tatecn]

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• Request a change to existing documentation
• Add new documentation
• Report a technical problem with the documentation
• Other

Tell us about your request. Provide a summary of the request.
I encountered an issue while using the logstash-output-opensearch plugin to process the geo_shape field.
It seems there are no examples or clear solutions addressing this problem.
Perhaps we could improve the documentation or provide an example to help clarify this.

I hope I could help improve.
Version: List the OpenSearch version to which this issue applies, e.g. 2.14, 2.12--2.14, or all.
2.11 or above, I use 2.11

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.
Relevant issue: Can't index document for geo_shape field using logstash jdbc input

[Naarcha-AWS]

@tatecn: Do you have more information on the problem you encountered? Specifically, do you have the response or error you encountered while trying to use the plugin?

[tatecn]

@tatecn: Do you have more information on the problem you encountered? Specifically, do you have the response or error you encountered while trying to use the plugin?

@Naarcha-AWS Here is the detailed output log:
[WARN ][logstash.outputs.opensearch][main][f935c916c86023cf18e395f59b3cdba568f48e610b7d2c85120e72db7784cbd1] Could not index event to OpenSearch.

{
  : status=>400,
  : action=>[
    "index",
    {
      : _id=>"1814625742831620096",
      : _index=>"geo_shape_bug_demo",
      : routing=>nil
    },
    {
      "jobGeoBounds"=>"{\"coordinates\":[[[-123.63249969482422,38.86429977416992],[-123.63249969482422,36.892974853515625],[-121.20817565917969,36.892974853515625],[-121.20817565917969,38.86429977416992],[-123.63249969482422,38.86429977416992]]],\"type\":\"polygon\"}",
      "jdNo"=>"1814625742831620096",
      "@version"=>"1",
      "@timestamp"=>2024-12-07T03: 40: 32.999588910Z
    }
  ],
  : response=>{
    "index"=>{
      "_index"=>"geo_shape_bug_demo",
      "_id"=>"1814625742831620096",
      "status"=>400,
      "error"=>{
        "type"=>"mapper_parsing_exception",
        "reason"=>"failed to parse field [jobGeoBounds] of type [geo_shape]",
        "caused_by"=>{
          "type"=>"parse_exception",
          "reason"=>"expected word but found: '{'"
        }
      }
    }
  }
}