Fixed wrong metrics "path" tag by using a custom tags provider

[ppatierno]

This PR is a workaround for #921 to revert back having the HTTP resource path in the path metrics tag instead of the complete URI (even together with the host and query parameters) as used by latest Vert.x versions.
It's also related to the issue vert-x3/vertx-micrometer-metrics#225 I opened on the Vert.x micrometer repo to get why they changed this way.

[scholzj]

The code looks good to me. But ... given we have the bug there since 0.20 -> should we wait for the Vert.x response and if they did it intentionally and not just as a but should we instead adjust our dashboards to Vert.x solution?

[ppatierno]

Yeah, I raised the PR just to make people aware of what was going to be a potential workaround.
We can wait for them of course but tbh if they are not going to fix that I am not sure the path tag provided by Vert.x is right. The HTTP resource path has its own meaning and it should not contain host and query parameters. So let's see how the discussion goes with them. My feeling is that they went this way because the commit change also moved from HttpServerRequest to use HttpRequest and this one doesn't expose path() but just uri(). Maybe they just didn't notice the implication of that. I think we should not change our dashboards but fixing the code (with them or by ourselves).

[ppatierno]

As per discussion on #921 I am going to close this PR. We prefer to have it fixed on dashboards or properly by Vert.x folks (still waiting for their answer).