chore(deps) Update dependency gulp-purgecss to v5

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
gulp-purgecss (source)	4.1.3 -> 5.0.0

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Release Notes

FullHuman/purgecss

### [`v5.0.0`](https://togithub.com/FullHuman/purgecss/blob/HEAD/CHANGELOG.md#​500-httpsgithubcomFullHumanpurgecsscomparev413v500-2022-09-13) [Compare Source](https://togithub.com/FullHuman/purgecss/compare/v4.1.3...v5.0.0) ##### Bug Fixes - add safelist variables to postcss-purgecss [#​840](https://togithub.com/FullHuman/purgecss/issues/840) ([c822058](https://togithub.com/FullHuman/purgecss/commit/c822058a703a0544c0bb683427937d9683688742)) - **gulp-purgecss:** support skippedContentGlobs option [#​853](https://togithub.com/FullHuman/purgecss/issues/853) ([b72de77](https://togithub.com/FullHuman/purgecss/commit/b72de77323fd74d5d53695409fef26e369656839)) - Purgecss webpack plugin/only filter fix ([#​933](https://togithub.com/FullHuman/purgecss/issues/933)) ([f8e4c2c](https://togithub.com/FullHuman/purgecss/commit/f8e4c2c48440c26ca612b2486a6e9561be6f56d0)) - **purgecss-webpack-plugin:** add sourcemap support [#​409](https://togithub.com/FullHuman/purgecss/issues/409) ([b3f73ed](https://togithub.com/FullHuman/purgecss/commit/b3f73ed5293fa1d840aff98b5796f635343d48ec)) - **purgecss-webpack-plugin:** export as named export as well as default ([#​821](https://togithub.com/FullHuman/purgecss/issues/821)) ([a6a2c8e](https://togithub.com/FullHuman/purgecss/commit/a6a2c8e0634324cc9ab276e02d5447d5d6c1e6e3)) - wrong path import ([4f3ddd0](https://togithub.com/FullHuman/purgecss/commit/4f3ddd0a47ec29cf8a723bd68ebc4b724e03dc7e)) ##### Features - add source map support [#​526](https://togithub.com/FullHuman/purgecss/issues/526) ([f2a9c5a](https://togithub.com/FullHuman/purgecss/commit/f2a9c5ac575af9a1e3f85be63b758fb9c37077e1)) - **gulp-purgecss:** add support for gulp-sourcemaps [#​257](https://togithub.com/FullHuman/purgecss/issues/257) ([55c26d2](https://togithub.com/FullHuman/purgecss/commit/55c26d2790b8502f115180cfe02aba5720c84b7b)) - **postcss-purgecss:** load options from purgecss config ([4de3bd8](https://togithub.com/FullHuman/purgecss/commit/4de3bd8e198985670502f77c57567eb43fcccbd4)) - **purgecss-webpack-plugin:** load config file automatically [#​767](https://togithub.com/FullHuman/purgecss/issues/767) ([726faaa](https://togithub.com/FullHuman/purgecss/commit/726faaa1e6eeb96f6c6b223d1ba925f9d7f33cba)) ##### BREAKING CHANGES - **purgecss-webpack-plugin:** drop webpack 4 support

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Configuration

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[christopherpickering]

:tada: This PR is included in version 3.10.7-alpha.1 :tada:

The release is available on GitHub release

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[christopherpickering]

:tada: This PR is included in version 3.10.7 :tada:

The release is available on GitHub release

Your semantic-release bot :package::rocket: