feat - check wrong connectionString syntax via host&port parse result

[LangInteger]

Motivation

Hey, I'm using vertx-redis-client in my project and I mistook the connection string from something like redis://domain:port to redis://:domain:port.

The weird thing is that the connection string with the wrong syntax worked, of course not to my specified host and port, but to the 127.0.0.1:6379. It spent me quite a while to figure out what happened there and I hope no other developers fall into the same trap again, so here comes the Pull Request.

Conformance

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