Describe the bug
While integrating Reactive spring security with observability, we got a code to create the bean of ObservationRegistryCustomizer in spring security reference document but in this code, we are trying to call ObservationTextHandler but this class is not available.

To Reproduce
Steps to reproduce the behavior.

Expected behavior
Provide the good sample bean creation while integrating with observability

Sample

A link to a GitHub repository with a minimal, reproducible sample.

Reports that include a sample will take priority over reports that do not.
At times, we may require a sample, so it is good to try and include a sample up front.