Return status.Errorf instead of plain errors from gRPC functions

[rkapka]

What type of PR is this?

Other

What does this PR do? Why is it needed?

It is not straightforward to reason about types of errors returned by gRPC functions when some code paths return status.Errorf and some return plain errors. The latter is correct when helper functions return status.Errorf, which is currently the case. It's also easier to make a mistake and use the wrong error type because there is no clear separation of responsibilities.

This PR simplifies things by always returning status.Errorf from top-level gRPC functions and plain errors from helper functions.

Which issues(s) does this PR fix?

N/A

Other notes for review

N/A

[codecov]

Codecov Report

Merging #8619 (8822228) into develop (034a287) will increase coverage by 0.07%.
The diff coverage is 28.57%.

@@             Coverage Diff             @@
##           develop    #8619      +/-   ##
===========================================
+ Coverage    61.28%   61.36%   +0.07%     
===========================================
  Files          488      488              
  Lines        34367    34307      -60     
===========================================
- Hits         21062    21052      -10     
+ Misses       10192    10146      -46     
+ Partials      3113     3109       -4