[DOC] Data Prepper regex and strings do not support $

[dlvenable]

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• [ ] Add new documentation
• [ ] Report a technical problem with the documentation
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Data Prepper strings do not support $. Some pages such as the following include $ in the regex pattern, but this does not work.

https://opensearch.org/docs/latest/data-prepper/pipelines/expression-syntax/

We should remove $ from these examples.

*Version: List the OpenSearch version to which this issue applies, e.g. 2.14, 2.12--2.14, or all.

All versions

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.

Data Prepper issue to add this support:

https://github.com/opensearch-project/data-prepper/issues/4772

[hdhalter]

@dlvenable, are you going to change the behavior (as per 4772) to add the support for $? If imminent, we should probably leave the docs as is. But, if it will take some time, we can remove them, and then add back once the functionality is added.

[natebower]

@dlvenable Closing as stale, but just ping me if you need this to stay open. Thanks!