Add kafka receiver flags to ingester

[pavolloffay]

Related to #2250

[codecov]

Codecov Report

Merging #2251 into master will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2251   +/-   ##
=======================================
  Coverage   96.16%   96.16%           
=======================================
  Files         219      219           
  Lines       10648    10650    +2     
=======================================
+ Hits        10240    10242    +2     
- Misses        352      353    +1     
+ Partials       56       55    -1     

Impacted Files	Coverage Δ
...lugin/sampling/strategystore/adaptive/processor.go	99.20% <0.00%> (-0.80%)	⬇️
cmd/collector/app/builder_flags.go	100.00% <0.00%> (ø)
cmd/query/app/static_handler.go	88.59% <0.00%> (+1.75%)	⬆️

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[objectiser]

Is it possibly to add a test?

[pavolloffay]

So far we haven't been testing main classes. The options/builder struct with flags should be tested in the original package.