Remove cweagans/composer-patches from Varbase Theme Admin

Problem/Motivation

Reported by Emircan ERKUL

- drupal/vartheme_admin[6.13.0, ..., 6.x-dev] require cweagans/composer-patches ~1 -> found cweagans/composer-patches[1.0.0, ..., 1.x-dev] but it conflicts with your root composer.json require (~2.0).

After #3437217: Switch to a local patching system using vardot/varbase-patches and cweagans/composer-patches ~2 within Varbase

cweagans/composer-patches 2.0.0-beta1 was released
https://github.com/cweagans/composer-patches/releases/tag/2.0.0-beta1
cweagans/composer-patches 2.0.0-beta2 was released
https://github.com/cweagans/composer-patches/releases/tag/2.0.0-beta2

Many improvements for the patching system.

Proposed resolution

• Remove cweagans/composer-patches from composer.json file.
• Pave the way for a smooth update for the patching system.

This is an old project
Removing the following

    "composer/installers": "~2",
    "oomphinc/composer-installers-extender": "~2",
    "cweagans/composer-patches": "~1",

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
• ➖ User Guide Documentation support on feature change/addition
• ➖ UX/UI designer responsibilities
• ➖ 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 vartheme_admin-8.x-6.14

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 #3440985 by emircanerkul: Removed cweagans/composer-patches from Varbase Theme Admin