Add prometheus app name to runtime metrics

[Jeymisson]

What is the purpose of this pull request?

1 - Upgrade prom-client to newest version
2 - Add prometheus app name to runtime metrics

What problem is this solving?

Enable runtime http metrics aggregation by app

How should this be manually tested?

1 - yarn link Inside node-vtex-api src dir
2 - yarn link @vtex/api at any app node dir of any IO node app, example: vtex.messages
3 - vtex link IO app
4 - see metrics at grafana or by forwarding linked pod to your localhost and accessing http://localhost:5050/metrics

Screenshots or example usage

Metrics usage example

Port forwarding & metrics exposure usage example

Types of changes

• Bug fix (a non-breaking change which fixes an issue)
• New feature (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Requires change to documentation, which has been updated accordingly.

[arturpimentel]

LGTM!