SASS deprecation warnings when running jekyll serve

[peterdesmet]

When running jekyll serve in a local site that makes use of the gem, I get the following deprecation warnings:

Deprecation Warning: $weight: Passing a number without unit % (100) is deprecated.

To preserve current behavior: $weight * 1%

More info: https://sass-lang.com/d/function-units

    ╷
201 │   @return mix(rgba($foreground, 1), $background, opacity($foreground) * 100);
    │           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    ╵
    /Users/peter_desmet/Coding/Repositories/peterdesmet/petridish/_sass/bootstrap/_functions.scss 201:11            opaque()
    /Users/peter_desmet/Coding/Repositories/peterdesmet/petridish/_sass/bootstrap/mixins/_table-variants.scss 4:28  table-variant()
    /Users/peter_desmet/Coding/Repositories/peterdesmet/petridish/_sass/bootstrap/_tables.scss 138:3                @import
    bootstrap/bootstrap.scss 22:9                                                                                   @import
    /Users/peter_desmet/Coding/Repositories/peterdesmet/mysite/assets/theme/css/main.scss 39:9                      root stylesheet
Deprecation Warning: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.

Recommendation: math.div($grid-gutter-width, 2) or calc($grid-gutter-width / 2)

More info and automated migrator: https://sass-lang.com/d/slash-div

   ╷
17 │   margin-bottom: $grid-gutter-width / 2;
   │                  ^^^^^^^^^^^^^^^^^^^^^^
   ╵
    _base.scss 17:18                                                                            @import
    /Users/peter_desmet/Coding/Repositories/peterdesmet/mysite/assets/theme/css/main.scss 44:9  root stylesheet
Deprecation Warning: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.

Recommendation: math.div($grid-gutter-width, 2) or calc($grid-gutter-width / 2)

More info and automated migrator: https://sass-lang.com/d/slash-div

  ╷
8 │   padding: $grid-gutter-width / 2 0;
  │            ^^^^^^^^^^^^^^^^^^^^^^
  ╵
    _footer.scss 8:12                                                                           @import
    /Users/peter_desmet/Coding/Repositories/peterdesmet/mysite/assets/theme/css/main.scss 52:9  root stylesheet

To investigate what Bootstrap uses