SCSS: Fix broken comments between declaration prop and value

[fisker]

Fixes #5603
Fixes #8052
Fixes #7109

• I’ve added tests to confirm my change works.
• (If changing the API or CLI) I’ve documented the changes I’ve made (in the docs/ directory)
• (If the change is user-facing) I’ve added my changes to changelog_unreleased/*/pr-XXXX.md file following changelog_unreleased/TEMPLATE.md.
• I’ve read the contributing guidelines.

✨Try the playground for this PR✨

[fisker]

I forgot mark this ready, this not prefect, but prints better.

[fisker]

I know this still ugly, but stable even worse

Prettier 2.0.5
Playground link

--parser scss

Input:

$font-family-rich:
  // custom
  'Noto Sans TC', 'Noto Sans SC', 'Noto Sans JP', 
  // Safari for OS X and iOS (San Francisco)
  -apple-system, BlinkMacSystemFont,
  // fallback
  Roboto, 'Helvetica Neue', Helvetica, Arial, sans-serif,
  // emoji
  'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol' !default;

Output:

$font-family-rich:
  // custom "Noto Sans TC", "Noto Sans SC", "Noto Sans JP",
  // Safari for OS X and iOS (San Francisco)
    -apple-system,
  BlinkMacSystemFont,
  // fallback
    Roboto,
  "Helvetica Neue", Helvetica, Arial, sans-serif,
  // emoji
    "Apple Color Emoji",
  "Segoe UI Emoji", "Segoe UI Symbol" !default;

[alexander-akait]

Not too bad

[alexander-akait]

We can improve it in the future, broken code is worse than ugly

[fisker]

Forgot changlog, will add tomorrow.