[EXPORTER] bump prometheus to v1.3.0

[esigo]

Fixes # (issue)

Changes

bumps prometheus from 1.2.4 to v1.3.0.

For significant contributions please make sure you have completed the following items:

• CHANGELOG.md updated for non-trivial changes
• Unit tests have been added
• Changes in public API reviewed

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.88%. Comparing base (497eaf4) to head (42d4950).
Report is 154 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3122      +/-   ##
==========================================
+ Coverage   87.12%   87.88%   +0.76%     
==========================================
  Files         200      195       -5     
  Lines        6109     6137      +28     
==========================================
+ Hits         5322     5393      +71     
+ Misses        787      744      -43     

see 99 files with indirect coverage changes

[marcalff]

LGTM, thanks for the upgrade.

Totally optional, please consider to add a section in file
docs/maintaining-dependencies.md as well, for prometheus-cpp.

[esigo]

@marcalff thanks, added a section in file docs/maintaining-dependencies.md, for prometheus-cpp.