docs: add missing full stop at the end of the configuration description

(cherry picked from commit e49991b)

Author: alan-agius4

packages/angular/cli/commands/definitions.json

@@ -14,7 +14,7 @@
           }
         },
         "configuration": {
-          "description": "One or more named builder configurations as a comma-separated list as specified in the \"configurations\" section of angular.json.\nThe builder uses the named configurations to run the given target.\nFor more information, see https://angular.io/guide/workspace-config#alternate-build-configurations.\nSetting this explicitly overrides the \"--prod\" flag",
+          "description": "One or more named builder configurations as a comma-separated list as specified in the \"configurations\" section of angular.json.\nThe builder uses the named configurations to run the given target.\nFor more information, see https://angular.io/guide/workspace-config#alternate-build-configurations.\nSetting this explicitly overrides the \"--prod\" flag.",
           "type": "string",
           "aliases": [
             "c"