build: update to cssnano to version 5.0.0

Closes #19106

Author: alan-agius4

package.json

@@ -138,7 +138,7 @@
     "core-js": "3.10.1",
     "critters": "0.0.10",
     "css-loader": "5.2.1",
-    "cssnano": "4.1.11",
+    "cssnano": "5.0.0",
     "debug": "^4.1.1",
     "enhanced-resolve": "5.7.0",
     "express": "4.17.1",

packages/angular_devkit/build_angular/package.json

@@ -31,7 +31,7 @@
     "core-js": "3.10.1",
     "critters": "0.0.10",
     "css-loader": "5.2.1",
-    "cssnano": "4.1.11",
+    "cssnano": "5.0.0",
     "find-cache-dir": "3.3.1",
     "glob": "7.1.6",
     "https-proxy-agent": "5.0.0",

packages/angular_devkit/build_angular/src/webpack/plugins/optimize-css-webpack-plugin.ts

@@ -87,9 +87,9 @@ export class OptimizeCssWebpackPlugin {
           };
 
           const output = await new Promise<Result>((resolve, reject) => {
-            // the last parameter is not in the typings
+            // @types/cssnano are not up to date with version 5.
             // tslint:disable-next-line: no-any
-            (cssNano.process as any)(content, postCssOptions, cssNanoOptions)
+            (cssNano as any)(cssNanoOptions).process(content, postCssOptions)
               .then(resolve)
               .catch((err: Error) => reject(new Error(`${file} ${err.message}`)));
           });