fix(deps): update dependency sass to v1.77.8 (#423)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [sass](https://togithub.com/sass/dart-sass) | [`1.77.5` ->
`1.77.8`](https://renovatebot.com/diffs/npm/sass/1.77.5/1.77.8) |
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|
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|
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|
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|

---

### Release Notes

<details>
<summary>sass/dart-sass (sass)</summary>

###
[`v1.77.8`](https://togithub.com/sass/dart-sass/blob/HEAD/CHANGELOG.md#1778)

[Compare
Source](https://togithub.com/sass/dart-sass/compare/1.77.7...1.77.8)

-   No user-visible changes.

###
[`v1.77.7`](https://togithub.com/sass/dart-sass/blob/HEAD/CHANGELOG.md#1777)

[Compare
Source](https://togithub.com/sass/dart-sass/compare/1.77.6...1.77.7)

- Declarations that appear after nested rules are deprecated, because
the
semantics Sass has historically used are different from the semantics
specified by CSS. In the future, Sass will adopt the standard CSS
semantics.

See [the Sass website](https://sass-lang.com/d/mixed-decls) for details.

- **Potentially breaking bug fix:** `//` in certain places such as
unknown
at-rule values was being preserved in the CSS output, leading to
potentially
invalid CSS. It's now properly parsed as a silent comment and omitted
from the
    CSS output.

###
[`v1.77.6`](https://togithub.com/sass/dart-sass/blob/HEAD/CHANGELOG.md#1776)

[Compare
Source](https://togithub.com/sass/dart-sass/compare/1.77.5...1.77.6)

- Fix a few cases where comments and occasionally even whitespace wasn't
allowed
    between the end of Sass statements and the following semicolon.

</details>

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