fix: scss warnings

[Schwehn42]

Description

Recently, the following warnings came up:

<w> 
<w> src/constants/colors.scss 235:11                                             set-base-colors()
<w> src/constants/colors.scss 255:3                                              @import
<w> src/constants/style.scss 4:9                                                 @import
<w> src/components/BoardHeader/HeaderMenu/BoardOptions/BoardOptionLink.scss 1:9  root stylesheet
<w> 
<w> You probably don't mean to use the color value gray in interpolation here.
<w> It may end up represented as gray, which will likely produce invalid CSS.
<w> Always quote color names when using them as strings or map keys (for example, "gray").
<w> If you really want to use the color value here, use '"" + $color-name'.

So I did as suggested and put the map keys "gray" and "navy" as quotes, which should hopefully fix it.

Also, another warning concerning rule order was fixed: https://sass-lang.com/d/mixed-decls

Changelog

• Put the map keys navy and gray in quotes
• change rule order: no declarations after nested rules

[github-actions]

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