Added limitation on pipelines not being able to read from variable libraries

Author: MicahRowlandMicrosoft

docs/security/security-workspace-level-private-links-support.md

@@ -338,6 +338,7 @@ For more information, see [Private links for Azure and Fabric Events](/fabric/re
 - For Data Engineering workloads:
    - To query Lakehouse files or tables from a workspace that has workspace-level private link enabled, you must create a cross-workspace managed private endpoint connection to access resources in the other workspace. <!--For instructions, see [Cross workspace communication](security-cross-workspace-communication.md).-->
    - You can use either relative or full paths to query files or tables within the same workspace, or use a cross-workspace managed private endpoint connection to access them from another workspace. To read files in a Lakehouse located in another workspace, use a fully qualified path that includes the workspace ID and lakehouse ID (not their display names). This approach ensures the Spark session can resolve the path correctly and avoids socket timeout errors. [Learn more](workspace-outbound-access-protection-data-engineering.md#understanding-file-path-behavior-in-fabric-notebooks).
+- Variable Libraries cannot be accessed from a Pipeline.
 - Current limitations for Private Link with an eventhouse:
    - Copilot features: Machine learning workloads might experience limited functionality due to a known regression.
    - Eventstream pull: Eventstream workloads don't currently support full polling functionality.