Bump protobuf-java from 2.6.1 to 3.15.3 in /java#31

dependabot[bot] wants to merge 1 commit into

mastermoazreyad/singa:masterfrom

7629dependabot/maven/java/com.google.protobuf-protobuf-java-3.15.3moazreyad/singa:7629dependabot/maven/java/com.google.protobuf-protobuf-java-3.15.3Copy head branch name to clipboard