Bump postcss from 8.1.4 to 8.1.6

Bumps [postcss](https://github.com/postcss/postcss) from 8.1.4 to 8.1.6.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/master/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/compare/8.1.4...8.1.6)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

yarn.lock

@@ -5426,7 +5426,7 @@ nanoid@3.1.12:
   resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.1.12.tgz#6f7736c62e8d39421601e4a0c77623a97ea69654"
   integrity sha512-1qstj9z5+x491jfiC4Nelk+f8XBad7LN20PmyWINJEMRSf3wcAjAWysw1qaA8z6NSKe2sjq1hRSDpBH5paCb6A==
 
-nanoid@^3.1.15:
+nanoid@^3.1.16:
   version "3.1.16"
   resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.1.16.tgz#b21f0a7d031196faf75314d7c65d36352beeef64"
   integrity sha512-+AK8MN0WHji40lj8AEuwLOvLSbWYApQpre/aFJZD71r43wVRLrOYS4FmJOPQYon1TqB462RzrrxlfA74XRES8w==
@@ -6082,13 +6082,13 @@ postcss-value-parser@^4.1.0:
   integrity sha512-97DXOFbQJhk71ne5/Mt6cOu6yxsSfM0QGQyl0L25Gca4yGWEGJaig7l7gbCX623VqTBNGLRLaVUCnNkcedlRSQ==
 
 postcss@^8.0.3:
-  version "8.1.4"
-  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.1.4.tgz#356dfef367a70f3d04347f74560c85846e20e4c1"
-  integrity sha512-LfqcwgMq9LOd8pX7K2+r2HPitlIGC5p6PoZhVELlqhh2YGDVcXKpkCseqan73Hrdik6nBd2OvoDPUaP/oMj9hQ==
+  version "8.1.6"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.1.6.tgz#b022ba2cfb8701da234d073ed3128c5a384c35ff"
+  integrity sha512-JuifSl4h8dJ70SiMXKjzCxhalE6p2TnMHuq9G8ftyXj2jg6SXzqCsEuxMj9RkmJoO5D+Z9YrWunNkxqpRT02qg==
   dependencies:
     colorette "^1.2.1"
     line-column "^1.0.2"
-    nanoid "^3.1.15"
+    nanoid "^3.1.16"
     source-map "^0.6.1"
 
 preact-render-to-string@^4.1.0: