ci: check unused package in go.mod

[seeflood]

Signed-off-by: seeflood [email protected]

What this PR does:

• Check unused package in submodules' go.mod .
  

• Fix some linter issues in submodules

Which issue(s) this PR fixes:

Fixes #597

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[codecov]

Codecov Report

Merging #595 (fd44251) into main (5bada7f) will increase coverage by 0.00%.
The diff coverage is 66.66%.

❗ Current head fd44251 differs from pull request most recent head ec14ff2. Consider uploading reports for the commit ec14ff2 to get more accurate results

@@           Coverage Diff           @@
##             main     #595   +/-   ##
=======================================
  Coverage   60.70%   60.70%           
=======================================
  Files         120      120           
  Lines        6382     6375    -7     
=======================================
- Hits         3874     3870    -4     
+ Misses       2139     2136    -3     
  Partials      369      369           

Impacted Files	Coverage Δ
components/file/hdfs/hdfs.go	46.15% <66.66%> (-0.63%)	⬇️

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[Xunzhuo]

lgtm