Remove logging from metrics methods

[thomshutt]

What does this pull request do? Explain your changes. (required)
Remove logging that's just recording the fact we've emitted a metric. All of the information in these lines is duplicated in other logging.

How did you test each of these updates (required)

• Ran unit tests

Does this pull request close any open issues?
No

Checklist:

• Read the contribution guide
• make runs successfully
• All tests in ./test.sh pass
• README and other documentation updated
• Pending changelog updated

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (3f4ee24) 56.33564% compared to head (5b505ea) 56.35850%.

Additional details and impacted files

@@                 Coverage Diff                 @@
##              master       #2948         +/-   ##
===================================================
+ Coverage   56.33564%   56.35850%   +0.02286%     
===================================================
  Files             89          89                 
  Lines          19485       19470         -15     
===================================================
- Hits           10977       10973          -4     
+ Misses          7898        7887         -11     
  Partials         610         610                 

Files	Coverage Δ
monitor/census.go	63.76471% <ø> (+0.43138%)	⬆️

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Files	Coverage Δ
monitor/census.go	63.76471% <ø> (+0.43138%)	⬆️