Mattermost Operator v1.0.0

[gabrieljackson]

This chart update does the following:

• Bumps the Mattermost Operator chart version to 1.0.0
• Deprecates and removes resources for the optional MinIO Operator
• Deprecates and removes resources for the optional MySQL Operator
• Deprecation instructions added to the README
• Deprecation checks added to the templating logic to attempt to prevent upgrades when configuration is invalid
• Instructions on how to update CRDs added to the README

Fixes https://mattermost.atlassian.net/browse/CLD-7015