Tailwind add text color design tokens to the preset

What does this MR do?

Update tailwind config to consume compiled token JSON and add text color design tokens to tailwind preset.

!3908 (merged) creates text.primary, text.secondary, and text.tertiary design tokens as part of the design token pilot &12381 (closed).

These design tokens are aliases for existing gray primitive/base color design tokens

{
  "text": {
    "primary": {
      "$value": "{gray.900}",
      "$type": "color",
      "themeable": true
    },
    "secondary": {
      "$value": "{gray.500}",
      "$type": "color",
      "themeable": true
    },
    "tertiary": {
      "$value": "{gray.400}",
      "$type": "color",
      "themeable": true
    }
  }
}

In order to use Tailwind to create utility classes from these design tokens they require the compiled values for each token:

Token	Equals	light	dark
text.primary	{gray.900}	#333238	#ececef
text.secondary	{gray.500}	#737278	#89888d
text.tertiary	{gray.400}	#89888d	#737278

Using ./dist/tokens/json/tokens.json exposed the compiled hex values for each design token, as well as the path which can be used to construct CSS custom property name for var(--design-token-name, #000) (or var(--design-token-name, #000) if prefix not false).

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