Update Simple OAuth (OAuth2) & OpenID Connect from ~5.0 to ~6.0

Problem/Motivation

Simple OAuth (OAuth2) & OpenID Connect 6.0.0-beta4 was released on: 18 Apr 2023 by: bojan_dev
https://www.drupal.org/project/simple_oauth/releases/6.0.0-beta4

#3261247: Implement OAuth 2.0 Security Best Current Practice
#3263651: Make registration possible in the authorize flow

#3263590: Decouple the scope definition and provide static/dynamic scope providers

#3284629: Make scope providers more flexible
Many more improvements

Proposed resolution

• Change drupal/simple_oauth to ~6.0 in the composer.json file.

Remaining tasks

• ✅ File an issue about this project
• ✅ Addition/Change/Update/Fix to this project
• ✅ Testing to ensure no regression
• ➖ Automated unit/functional testing coverage
• ✅ Developer Documentation support on feature change/addition
  
  Changed
  Varbase API
• ➖ User Guide Documentation support on feature change/addition
• ➖ Accessibility and Readability
• ✅ Code review from 1 Varbase core team member
• ✅ Full testing and approval
• ✅ Credit contributors
• ✅ Review with the product owner
• ✅ Update Release Notes and Update Helper on new feature change/addition
• ✅ Release Varbase 10.0.0-alpha2, varbase_api-10.0.0-alpha2

Varbase update type

• ✅ No Update
• ➖ Optional Update
• ➖ Forced Update
• ➖ Forced Update if Unchanged

User interface changes

• N/A

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• Issue #3365138: Updated Simple OAuth (OAuth2) & OpenID Connect from ~5.0 to ~6.0
  
  Changed
  Varbase API