feat(tools/tokens): flutter support

[chreble]

I have read the contributing guidelines

• [x] Yes
• [ ] No

Does this PR introduce a breaking change?

• [ ] Yes
• [x] No

Describe the changes

Add flutter design tokens in the generator.

[mohamedMok]

Checkmarx One – Scan Summary & Details – 14cd2493-a37f-4cc2-be22-6d6eb8a3934e

New Issues

Severity	Issue	Source File / Package	Checkmarx Insight
	Cx366abb53-9fde	Npm-es5-ext-0.10.62	Vulnerable Package
	Cx73b00837-2300	Npm-styled-components-5.3.6	Vulnerable Package