Update golangci config

[chung-coder]

Description

This PR fixes #693

Notes for Reviewers
This PR updates golangci.yml by replacing deprecated linters and refining linting configurations for better code quality.

Before:

• Running golangci-lint config verify resulted in errors due to incorrect or incompatible configuration.
• Linters like golint and scopelint were used, but they were deprecated and caused validation issues.
• The configuration had overlapping or conflicting settings for certain linters.

After:

• Replaced deprecated linters:

  • golint → revive for better configurability and active maintenance.
  • scopelint → copyloopvar to improve variable scope analysis.

• Updated golangci.yml settings:

  • Corrected and simplified the configuration for revive, govet, unused, and cyclop.
  • Explicitly set rules for revive to enforce line-length-limit: 120.
  • Removed unnecessary settings and streamlined the linter configurations to avoid conflicts.

• Fixed validation issues:

  • Configured exclude-rules to exclude _test.go files from testpackage linter, preventing unnecessary checks for test files.
  • Adjusted the cyclop complexity limit to 7 for improved analysis.

Signed commits

• Yes, I signed my commits.

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[leecalcote]

Thank you, @chung-coder!

Will you:

1. Review our approach to golanglint-ci in the https://github.com/meshery/meshery repo? We'll want to ensure a consistent approach, making changes here, there, or both places.
2. Will you sign your commit? One-time instructions here. Permanent instructions here.

[hortison]

No response from @chung-coder

[hortison]

Marking PR as abandoned...