[YUNIKORN-3345] Turn on nonamedreturns linter

[PoiBlackTea]

Description

This PR turns on the nonamedreturns linter in .golangci.yml and refactors existing functions.

Type of change

Please delete options that are not relevant.

• Bug Fix
• Improvement
• Feature
• Refactoring
• Documentation

Jira issue

Jira ID : https://issues.apache.org/jira/browse/YUNIKORN-3345

• I have created a Jira issue for this pull request.
• The Jira ID is part of the title of this pull request.

AI Tooling

If an AI tool was used:

• The PR includes the phrase "Generated by Antigravity IDE", where Antigravity IDE is the name of the AI tool used.
• My use of AI contributions follows the ASF legal policy.

Check https://www.apache.org/legal/generative-tooling.html for details.

How has this been tested?

• New unit tests were added to cover new or changed code paths.
• make test_all was run, and no failures reported.
• A pull request will be opened for new e2e tests (apache/yunikorn-k8shim repository).

Questions:

• The change needs documentation, a pull request for apache/yunikorn-site repository will be created.
• There is breaking changes for older versions: jira is tagged with release-notes label.
• The licenses files needs to be updated.

Screenshots or other details

N/A

[codecov]

Codecov Report

❌ Patch coverage is 91.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 81.61%. Comparing base (ffab939) to head (f47638c).

Files with missing lines	Patch %	Lines
pkg/locking/locking.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1129   +/-   ##
=======================================
  Coverage   81.60%   81.61%           
=======================================
  Files         104      104           
  Lines       14251    14255    +4     
=======================================
+ Hits        11630    11634    +4     
  Misses       2331     2331           
  Partials      290      290           

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[manirajv06]

looks good