feat: release version 7

* Updates to Angular 12 and the component to version 7.
* Fixes that the rounded stroke is visible when the value is zero.
* Fixes that the `onRender` event was being emitted when there are no subscribers to it.

Author: crisbeto

angular.json

@@ -19,12 +19,17 @@
             "main": "src/demo/main.ts",
             "polyfills": "src/demo/polyfills.ts",
             "tsConfig": "tsconfig.app.json",
-            "aot": true,
             "assets": [],
             "styles": [
               "src/demo/styles.css"
             ],
-            "scripts": []
+            "scripts": [],
+            "vendorChunk": true,
+            "extractLicenses": false,
+            "buildOptimizer": false,
+            "sourceMap": true,
+            "optimization": false,
+            "namedChunks": true
           },
           "configurations": {
             "production": {
@@ -38,7 +43,6 @@
               "outputHashing": "all",
               "sourceMap": false,
               "namedChunks": false,
-              "extractLicenses": false,
               "vendorChunk": false,
               "buildOptimizer": true,
               "budgets": [
@@ -54,7 +58,8 @@
                 }
               ]
             }
-          }
+          },
+          "defaultConfiguration": ""
         },
         "serve": {
           "builder": "@angular-devkit/build-angular:dev-server",