buildscripts: sonatype uploader ussing CONF before it is set (#4388)
buildscripts: sonatype uploader ussing CONF before it is set (#4388)

Set $CONF before we use it.
Also enable some defensive bash flags to catch errors.
Default value for USER and PASS

ejona86/grpc-java,dapengzhang0/grpc-java,elandau/grpc-java,ejona86/grpc-java,zhangkun83/grpc-java,zhangkun83/grpc-java,carl-mastrangelo/grpc-java,grpc/grpc-java,ejona86/grpc-java,dapengzhang0/grpc-java,elandau/grpc-java,dapengzhang0/grpc-java,carl-mastrangelo/grpc-java,stanley-cheung/grpc-java,stanley-cheung/grpc-java,ejona86/grpc-java,zhangkun83/grpc-java,grpc/grpc-java,grpc/grpc-java,elandau/grpc-java,dapengzhang0/grpc-java,grpc/grpc-java,carl-mastrangelo/grpc-java,stanley-cheung/grpc-java,elandau/grpc-java,zhangkun83/grpc-java,carl-mastrangelo/grpc-java,stanley-cheung/grpc-java