Readme improvement for multi-select fields

[dkrones]

https://github.com/OpsLevel/community-integrations/blame/a1d5ad15daa14bc4f0078f194e65df2787cd3e58/custom_integration_mapping/PII-Dependency-Awareness/README.md#L78

If you allow multi-select in the Data Classification field, this check should normalize the value before comparing it. For example:

| (.value | fromjson | any(. == "Confidential"))

Otherwise, a value like ["Confidential","Operational Data (Logs, Metrics)"] won’t match correctly.