Update dependency clean-css to v4.2.4

Author: renovate[bot]

yarn.lock

@@ -1010,9 +1010,9 @@ ci-info@^3.1.1:
   integrity sha512-dVqRX7fLUm8J6FgHJ418XuIgDLZDkYcDFTeL6TA2gt5WlIZUQrrH6EZrNClwT/H0FateUsZkGIOPRrLbP+PR9A==
 
 clean-css@^4.1.11, clean-css@^4.2.1:
-  version "4.2.3"
-  resolved "https://registry.yarnpkg.com/clean-css/-/clean-css-4.2.3.tgz#507b5de7d97b48ee53d84adb0160ff6216380f78"
-  integrity sha512-VcMWDN54ZN/DS+g58HYL5/n4Zrqe8vHJpGA8KdgUXFU4fuP/aHNw8eld9SyEIyabIMJX/0RaY/fplOo5hYLSFA==
+  version "4.2.4"
+  resolved "https://registry.yarnpkg.com/clean-css/-/clean-css-4.2.4.tgz#733bf46eba4e607c6891ea57c24a989356831178"
+  integrity sha512-EJUDT7nDVFDvaQgAo2G/PJvxmp1o/c6iXLbswsBbUFXi1Nr+AjA2cKmfbKDMjMvzEe75g3P6JkaDDAKk96A85A==
   dependencies:
     source-map "~0.6.0"