Apply modernize suggestions

[AnnaShaleva]

Ref. nspcc-dev/.github#45.

[codecov]

Codecov Report

❌ Patch coverage is 25.00000% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 25.83%. Comparing base (afe088f) to head (5342d8c).
⚠️ Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
cmd/neofs-adm/internal/modules/fschain/deploy.go	0.00%	2 Missing ⚠️
cmd/neofs-adm/internal/modules/storagecfg/root.go	0.00%	2 Missing ⚠️
pkg/innerring/internal/blockchain/blockchain.go	0.00%	1 Missing ⚠️
pkg/morph/client/netmap/add_peer.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3853      +/-   ##
==========================================
- Coverage   25.86%   25.83%   -0.03%     
==========================================
  Files         669      669              
  Lines       43065    43058       -7     
==========================================
- Hits        11137    11126      -11     
- Misses      30914    30915       +1     
- Partials     1014     1017       +3     

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.