Add Contributor Guide

[christian-bromann]

Proposed changes

This patch adds a contributor guide that should help people making their first contribution to the project. Compared to the CONTRIBUTING.md which is more like contributor documentation the guide should give more information about the process of contributing to the project without going into technical details or governance too much.

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• I have added proper type definitions for new commands (if appropriate)

Further comments

Reviewers: @webdriverio/technical-committee

[codecov]

Codecov Report

Merging #5045 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #5045      +/-   ##
==========================================
- Coverage    99.4%   99.39%   -0.01%     
==========================================
  Files         210      210              
  Lines        5510     5612     +102     
  Branches     1180     1211      +31     
==========================================
+ Hits         5477     5578     +101     
- Misses         30       31       +1     
  Partials        3        3

Impacted Files	Coverage Δ
packages/wdio-cli/src/constants.js	80% <0%> (-8.89%)	⬇️
...kages/webdriverio/src/commands/element/addValue.js	100% <0%> (ø)	⬆️
packages/wdio-sauce-service/src/launcher.js	100% <0%> (ø)	⬆️
packages/wdio-runner/src/utils.js	100% <0%> (ø)	⬆️
packages/wdio-appium-service/src/launcher.js	100% <0%> (ø)	⬆️
...s/wdio-selenium-standalone-service/src/launcher.js	100% <0%> (ø)	⬆️
packages/wdio-testingbot-service/src/launcher.js	100% <0%> (ø)	⬆️

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[erwinheitzman]

Added one suggestion, please let me know if we want to change this after which I will approve :)

[christian-bromann]

@erwinheitzman updated docs and removed Chai.

[erwinheitzman]

LGTM :)