/variable-fonts/LICENSE.MD Updated

[davelab6]

What this PR does

Improves attribution and states the license of Decovar font

Requirements

• [x] My PR follows all applicable accessibility requirements (See .github/ACCESSIBILITY_REQS.md).
• [x] My PR follows the CSS code style guidelines (See .github/CSS_STYLE_REQS.md).
• [x] I have linted my code using npm run lint:css -- demoDirectoryName/**/*.css and npm run lint:js -- demoDirectoryName/**/*.js, and have fixed the errors.