Revert back to using :latest stack images in java11 builder.toml
Revert back to using :latest stack images in java11 builder.toml

PiperOrigin-RevId: 350182970
Change-Id: Ib2033e50605b929e77a8b80eb99d26798ae7112e

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