Bump clean-css from 4.2.3 to 5.1.2

[dependabot-preview]

Bumps clean-css from 4.2.3 to 5.1.2.

Changelog

Sourced from clean-css's changelog.

5.1.2 / 2021-03-19

• Fixed issue #996 - space removed from pseudo classes.

5.1.1 / 2021-03-03

• Fixed issue #1156 - invalid hsl/hsla validation in level 2 optimizations.

5.1.0 / 2021-02-18

• Fixes stripping '%' from inside color functions.
• Improves tokenization speed by ~30%.
• Fixed issue #1143 - some missing level 1 value optimizations.

5.0.1 / 2021-01-29

• Fixed issue #1139 - overriding & merging properties without canOverride set.

5.0.0 / 2021-01-29

• Adds a way process input files without bundling it into one big output file.
• Adds level 1 and level 2 optimization plugins.
• Disables URL rebasing by default.
• Disables URL unquoting by default.
• Drops support for Node.js 6 & 8 to support last 3 Node.js releases: 10, 12, and 14.
• Fixed issue #889 - whitelisted level 1 optimizations.
• Fixed issue #975 - incorrect block name optimization.
• Fixed issue #1009 - whitespace around comments.
• Fixed issue #1021 - allow one- and two-letter property names.
• Fixed issue #1022 - merging into shorthands new property positioning.
• Fixed issue #1032 - wrong order of merged shorthands with inherit.
• Fixed issue #1043 - calc fallback removed within other function.
• Fixed issue #1045 - non-standard protocol-less URL first slash removed.
• Fixed issue #1050 - correctly keeps default animation duration if delay is also set.
• Fixed issue #1053 - treats calc() as first class width value.
• Fixed issue #1055 - supports 4- and 8-character hex with alpha color notation.
• Fixed issue #1057 - level 2 optimizations and quoted font family name.
• Fixed issue #1059 - animation time units as CSS expressions.
• Fixed issue #1060 - variable removed when shorthand's only value.
• Fixed issue #1062 - wrong optimization of CSS pseudo-classes with selector list.
• Fixed issue #1073 - adds support for non-standard rpx units.
• Fixed issue #1075 - media merging and variables.
• Fixed issue #1087 - allow units with any case.
• Fixed issue #1088 - building source maps with source preserved via comments.

... (truncated)

Commits

• aa250dd Version 5.1.2.
• 5d7d6aa Fixes #996 - outstanding issue with spaces removed inside pseudoclasses.
• ebf9ea7 Bumps web interface to version 5.1.1.
• 896945f Version 5.1.1.
• a7cdd76 Fixes #1156 - invalid hsl/hsla validation in level 2 optimizations.
• 2a03edb Bumps web interface to version 5.1.0.
• 5f4fe15 Version 5.1.0.
• 12d16d5 Fixes #1143 - some missing level 1 value optimizations.
• a0e61fe Adds bootstrap v5 as a test fixture.
• d9ab4b4 Fixes stripping '%' from inside color functions.
• Additional commits viewable in compare view

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