chore(Dockerfile): revert registry.suse.com/bci/bci-base to 15.7

registry.suse.com/bci/bci-base:15.6 is still in Tech Preview

Signed-off-by: Derek Su <[email protected]>

Author: derekbit

package/Dockerfile

@@ -12,7 +12,7 @@ RUN chmod +x /app/scripts/build
 # Run the build script
 RUN /app/scripts/build
 
-FROM registry.suse.com/bci/bci-base:15.7
+FROM registry.suse.com/bci/bci-base:15.6
 
 ARG TARGETPLATFORM
 RUN if [ "$TARGETPLATFORM" != "linux/amd64" ] && [ "$TARGETPLATFORM" != "linux/arm64" ]; then \