public Builder setAlwaysCacheBaseImage(boolean alwaysCacheBaseImage) {
      this.alwaysCacheBaseImage = alwaysCacheBaseImage;
      return this;
    }
Controls the optimization which skips downloading base image layers that exist in a target
registry. If the user does not set this property then read as false.

@param alwaysCacheBaseImage if {@code true}, base image layers are always pulled and cached.
    If {@code false}, base image layers will not be pulled/cached if they already exist on
    the target registry.
@return this
jib-core/src/main/java/com/google/cloud/tools/jib/configuration/BuildContext.java