added ruby client compression interop tests

src/ruby/bin/math_services.rb

src/ruby/ext/grpc/rb_call.c

src/ruby/pb/src/proto/grpc/testing/messages.rb

src/ruby/pb/test/client.rb

src/ruby/pb/test/proto/empty.rb

src/ruby/pb/test/proto/messages.rb

src/ruby/pb/test/proto/test.rb

src/ruby/pb/test/proto/test_services.rb

src/ruby/pb/test/server.rb

src/ruby/qps/src/proto/grpc/testing/messages.rb

tools/run_tests/run_interop_tests.py