Modify golangci.yaml file. Resolve found lint issues.

[blackpiglet]

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Please add a summary of your change

Remove the enabled linters setting from Makefile. Move the enabled linters list into golangci.yaml.
Enable more linters, including bodyclose, goheader, misspell, typecheck and unused.

Fix found issues found by linters.

Does your change fix a particular issue?

Fixes #6024

Please indicate you've done the following:

• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• Updated the corresponding documentation in site/content/docs/main.

[codecov-commenter]

Codecov Report

Merging #6008 (4800a2d) into main (8235866) will increase coverage by 0.03%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main    #6008      +/-   ##
==========================================
+ Coverage   41.26%   41.29%   +0.03%     
==========================================
  Files         252      251       -1     
  Lines       23380    23369      -11     
==========================================
+ Hits         9647     9650       +3     
+ Misses      12974    12961      -13     
+ Partials      759      758       -1     

Impacted Files	Coverage Δ
pkg/builder/json_schema_props_builder.go	0.00% <ø> (ø)
pkg/cmd/cli/backuplocation/delete.go	0.00% <0.00%> (ø)
pkg/cmd/cli/nodeagent/server.go	12.44% <0.00%> (-0.29%)	⬇️
pkg/cmd/server/server.go	5.20% <0.00%> (-0.08%)	⬇️
pkg/controller/backup_deletion_controller.go	57.26% <0.00%> (ø)
pkg/restic/exec_commands.go	15.21% <0.00%> (ø)
pkg/restore/change_pvc_node_selector.go	62.50% <ø> (ø)
pkg/restore/priority.go	95.00% <ø> (ø)
pkg/restore/restore.go	64.86% <0.00%> (+0.52%)	⬆️
pkg/uploader/kopia/progress.go	0.00% <ø> (ø)
... and 6 more

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