Don't add spaces to gradients and grid track names when followed by calc()

[thecrypticace]

We do spacing normalization around operators so you can write things like w-[calc(100%-2px)] and not have to worry about inserting spaces. We use a combination of regex and a mini lexer for this but the regexes are prone to over matching.

This PR adds a targeted fix that prevents us from inserting spaces for the following CSS functions:

• radial-gradient
• linear-gradient
• conic-gradient
• repeating-radial-gradient
• repeating-linear-gradient
• repeating-conic-gradient

Additionally, I've added a fix that prevents the addition of spaces around - when inside a CSS grid track name that's encased in square brackets.

Before:

.bg-\[radial-gradient\(calc\(\)\)\2c radial-gradient\(calc\(\)\)\]{
  background-image: radial-gradient(calc()),radial - gradient(calc())
}

.grid-cols-\[\[content-start\]_calc\(100\%-1px\)_\[content-end\]_calc\(1rem\+1px\)\]{
  grid-template-columns: [content-start] calc(100% - 1px) [content - end] calc(1rem + 1px)
}

After:

.bg-\[radial-gradient\(calc\(\)\)\2c radial-gradient\(calc\(\)\)\]{
  background-image: radial-gradient(calc()),radial-gradient(calc())
}

.grid-cols-\[\[content-start\]_calc\(100\%-1px\)_\[content-end\]_calc\(1rem\+1px\)\]{
  grid-template-columns: [content-start] calc(100% - 1px) [content-end] calc(1rem + 1px)
}

An even better solution would be to eventually introduce a lexer that's more top-level and understands CSS function syntax but that will have to happen another day.

Fixes #12654
Fixes #12665