Broaden composer compatibility

Problem/Motivation

Remove strict requirements in composer, especially for packages that aren't a code dependency for Vardot Support.

Proposed resolution

• Use wildcard versions for packages that aren't a code dependency for Vardot Support.

Change to

    "require": {
        "drupal/raven": "@stable",
        "drupal/site_audit": "@stable",
        "drupal/seckit": "@stable",
        "drupal/security_review": "@stable",
        "drupal/admin_toolbar": "@stable",
        "drupal/flood_control": "@stable",
        "drush/drush": "@stable",
        "drupal/stage_file_proxy": "@stable",
        "pyrech/composer-changelogs": "@stable",
        "vlucas/phpdotenv": "@stable",
        "drupal/site": "~2.0"
    },

• Remove the Backup and Migrate module.
• Remove the Flysystem module
• Remove the platformsh/config-reader library. ( It is already in the vardot/platformsh-varbase ) an not needed for projects in Acquia hosting, OVH, or other hosting setup
• Remove the league/flysystem-sftp deprecated/abandoned library

Manage to have the module required and installed under Drupal 8, Drupal 9, and Drupal 10 sites.

#3368035: Plan: Release Vardot Support 1.1.0-rc1 or 1.1.0 stable

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
• ➖ 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 vardot_support-1.1.0-beta6, vardot_support-1.1.0-beta7

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 #3392028: Broadened composer compatibility