Update a comment instructing engineers to use a deprecated function
Update a comment instructing engineers to use a deprecated function

PiperOrigin-RevId: 300165270
Change-Id: If61de14910f2bb5204189d256ba1dab59e01cb08

GoogleCloudPlatform/buildpacks,GoogleCloudPlatform/buildpacks,GoogleCloudPlatform/buildpacks,GoogleCloudPlatform/buildpacks