docs: add quotes around example invocation for google cloud retry join
docs: add quotes around example invocation for google cloud retry join

kingland/consul,kingland/consul,scalp42/consul,scalp42/consul,vamage/consul,scalp42/consul,youhong316/consul,42wim/consul,calgaryscientific/consul,youhong316/consul,hashicorp/consul,calgaryscientific/consul,42wim/consul,vamage/consul,scalp42/consul,youhong316/consul,calgaryscientific/consul,i0rek/consul,hashicorp/consul,kingland/consul,youhong316/consul,i0rek/consul,calgaryscientific/consul,kingland/consul,vamage/consul,vamage/consul,vamage/consul,i0rek/consul,kingland/consul,42wim/consul,calgaryscientific/consul,i0rek/consul,youhong316/consul,42wim/consul,scalp42/consul,i0rek/consul,42wim/consul,hashicorp/consul,hashicorp/consul