fix install java protoc (#1720)

Author: typhoonzero

scripts/docker/install-java.bash

@@ -17,8 +17,8 @@ set -e
 
 apt-get -qq update && apt-get install -y openjdk-8-jdk maven > /dev/null
 
-# Install gRPC for Java as a protobuf-compiler plugin. c.f. https://stackoverflow# .com/a/53982507/724872.
-wget -q http://central.maven.org/maven2/io/grpc/protoc-gen-grpc-java/1.21.0/protoc-gen-grpc-java-1.21.0-linux-x86_64.exe
+# Install gRPC for Java as a protobuf-compiler plugin. c.f. https://stackoverflow.com/a/53982507/724872.
+wget -q https://repo1.maven.org/maven2/io/grpc/protoc-gen-grpc-java/1.21.0/protoc-gen-grpc-java-1.21.0-linux-x86_64.exe --no-check-certificate
 mv protoc-gen-grpc-java-1.21.0-linux-x86_64.exe /usr/local/bin/protoc-gen-grpc-java
 chmod +x /usr/local/bin/protoc-gen-grpc-java