Reformat rgba() colors

[simurai]

This closes #1778 and prevent Jekyll to throw the following error:

/usr/gem/gems/jekyll-sass-converter-1.5.2/lib/jekyll/converters/scss.rb:123:in `rescue in convert': wrong number of arguments (1 for 4) for `rgba' on line 16 (Jekyll::Converters::Scss::SyntaxError)

[changeset-bot]

🦋 Changeset detected

Latest commit: 1bc4dc4

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/css	Patch

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[tobiasahlin]

This is just standard functional color syntax - the Jekyll error being thrown here is from an old version (2018) of this gem. Latest is 2.1.0 → https://rubygems.org/gems/jekyll-sass-converter, could be worth verifying if this is a problem on newer versions before changing.

[svrooij]

This is just standard functional color syntax - the Jekyll error being thrown here is from an old version (2018) of this gem. Latest is 2.1.0 → https://rubygems.org/gems/jekyll-sass-converter, could be worth verifying if this is a problem on newer versions before changing.

It might be an old version, but version 1.5.2 is the one that is pulled in by github-pages according to github-pages gem. And there is nothing in the release notes suggesting that they implemented any other function parsing.

source 'https://rubygems.org'
gem 'github-pages', group: :jekyll_plugins
gem "jekyll-github-metadata"
gem "jekyll-octicons"
gem "jemoji"
gem "jekyll-paginate"