feat: upgrade CI to Node.js 20, update GitHub Actions versions, and restrict CI triggers

[Copilot]

fix: #74

Consolidates all CI jobs to Node.js 20 only, upgrades all GitHub Actions to their latest stable versions, and restricts CI workflow triggers to run only on master branch pushes and pull requests.

Changes

Node.js Version Updates

• lint job: Added explicit Node.js 20 version specification
• test job: Removed Node.js 18 from matrix, now runs only on Node.js 20

All jobs (lint, coverage, test, semantic-release) now consistently use Node.js 20.

GitHub Actions Version Updates

• actions/checkout: Upgraded from v2 to v4 (all 4 instances)
• actions/setup-node: Upgraded from v2.1.5 and v3 to v4 (all 4 instances)
• coverallsapp/github-action: Upgraded from master to v2
• mirromutth/mysql-action: Kept at v1.1 (already at latest stable version)

CI Trigger Configuration

• Workflow triggers: Changed from on: [push, pull_request] to only run on:
  • Pushes to master branch
  • All pull requests

This prevents unnecessary CI runs on pushes to feature branches, reducing CI resource usage.

[hsluoyz]

@nodece @Shivansh-yadav13 please review

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[hsluoyz]

@copilot also need to upgrade the used actions' versions in the CI scripts

[Copilot]

@copilot also need to upgrade the used actions' versions in the CI scripts

Done! Upgraded all GitHub Actions to latest stable versions in commit e1fe4aa:

• actions/checkout: v2 → v4
• actions/setup-node: v2.1.5/v3 → v4
• coverallsapp/github-action: master → v2

[hsluoyz]

@copilot - also need to only run CI for only pull requests and pushes to the master branch (so push to other branches won't run CI)

on:
push:
branches:
- master
pull_request:

[Copilot]

@copilot - also need to only run CI for only pull requests and pushes to the master branch (so push to other branches won't run CI)

on:
...

Done! Updated CI trigger configuration in commit 569a1ae. The workflow now only runs on:

• Pushes to master branch
• All pull requests