Add OpenObserve as an officially supported sink

[chaitanya-sistla]

This PR adds OpenObserve as an officially supported sink in Vector's documentation. OpenObserve utilizes an HTTP-based API for data ingestion, and this PR proposes updating the documentation with an example configuration for users to follow.

No new functionality is required, as the current HTTP sink already serves the purpose effectively. The primary goal is to improve user experience by offering clear guidance for setting up Vector with OpenObserve, ensuring confidence in its usage as a supported observability solution.

type = "http"
inputs = [ "source_or_transform_id" ]
uri = "http://localhost:5080/api/default/default/_json"
method = "post"
auth.strategy = "basic"
auth.user = "[email protected]"
auth.password = "v9Ca7qHaMKELlDtU" (fake)
compression = "gzip"
encoding.codec = "json"
encoding.timestamp_format = "rfc3339"
healthcheck.enabled = false

Why This Matters?
By officially documenting OpenObserve as a supported sink, we provide clear setup instructions for users, allowing them to confidently configure Vector for OpenObserve.

[bits-bot]

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