chore(tm2): add prometheus exporter

[albttx]

This PR add a prometheus exporter, and keep the current opentelemetry exporter.

Both can live side by side.

I understand opentelemetry, but it's really more convinient to have a prometheus exporter which is a "default" you find everywhere.

This PR also add a new metrics for Block Interval

This is a first draft, let's discuss about it

Contributors' checklist...

• Added new tests, or not needed, or not feasible
• Provided an example (e.g. screenshot) to aid review or the PR is self-explanatory
• Updated the official documentation or not needed
• No breaking changes were made, or a BREAKING CHANGE: xxx message was included in the description
• Added references to related issues and PRs
• Provided any useful hints for running manual tests
• Added new benchmarks to generated graphs, if any. More info here.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 48.38%. Comparing base (6482c18) to head (d8436a2).
Report is 6 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2032      +/-   ##
==========================================
+ Coverage   47.29%   48.38%   +1.08%     
==========================================
  Files         362      409      +47     
  Lines       58590    62036    +3446     
==========================================
+ Hits        27713    30019    +2306     
- Misses      28594    29517     +923     
- Partials     2283     2500     +217     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[albttx]

following internal discussion with @zivkovicmilos and @ajnavarro decision taken is to continue with OTEL, closing this