Automated headless web executions are x2 time on GitHub

The same tests takes 6 minutes locally but +15-20 minutes on GitHub increasing our time executions drastically and consuming our monthly GitHub Actions minutes within first days per month.

I have used GitHub and Bitbucket to run automated tests using different frameworks without issues. I’m lacking of ideas of what could be causing this very bad/low performance in GitHub.

Any ideas please?
Thank you

Automation framework used

        browserName: 'chrome',
         'goog:chromeOptions': {
             args: [ 
                '--headless',
                '--disable-gl-drawing-for-tests',
                '--log-level=3' //INFO = 0, WARNING = 1, LOG_ERROR = 2, LOG_FATAL = 3
                ]
         },

workflow.yml

# This is a basic workflow to help you get started with Actions 

name: regression

# Controls when the workflow will run
on:
  schedule:
    - cron: '0 10 * * 1-5'
    - cron: '0 15 * * 1-5'
    - cron: '0 20 * * 1-5'

  # Allows you to run this workflow manually from the Actions tab
  workflow_dispatch:

jobs:
  Automation_Regression_Suite:
    name: automation regression suite
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2
      - name: NPM install
        run: npm i && npm fund && npm audit fix
      - name: Run automation regression suite
        run: npx wdio ./src/config/wdio.conf.stg.js --mochaOpts.grep "@regression"