Fix broken links to openservicemesh/osm docs

References to the following links are broken:

https://github.com/openservicemesh/osm/blob/main/docs/upgrade_guide.md#crd-upgrades (https://github.com/Azure/osm-azure/blob/d64f17885c237bb7e0f96d966c9bba9c58d308fa/docs/update-extension.md#L9)

https://github.com/openservicemesh/osm/blob/main/docs/uninstallation_guide.md (https://github.com/Azure/osm-azure/blob/d64f17885c237bb7e0f96d966c9bba9c58d308fa/docs/delete-extension.md#L11)

Start with docs/update-extension.md#L9 and docs/delete-extension.md#L11, then verify the referenced Open Service Mesh documentation paths. Update both broken references to valid documentation URLs and confirm that the links resolve.

Written by the indexing model from the issue text.