add CLI argument --disable-workspace-trust (#5638)

Add CLI flag to disable workspace trust feature, as
described in documentation:
https://code.visualstudio.com/docs/editor/workspace-trust

Add test for workspace trust argument.

src/node/cli.ts

@@ -50,6 +50,7 @@ export interface UserProvidedCodeArgs {
   "github-auth"?: string
   "disable-update-check"?: boolean
   "disable-file-downloads"?: boolean
+  "disable-workspace-trust"?: boolean
 }
 
 /**
@@ -163,6 +164,10 @@ export const options: Options<Required<UserProvidedArgs>> = {
     description:
       "Disable file downloads from Code. This can also be set with CS_DISABLE_FILE_DOWNLOADS set to 'true' or '1'.",
   },
+  "disable-workspace-trust": {
+    type: "boolean",
+    description: "Disable Workspace Trust feature. This switch only affects the current session.",
+  },
   // --enable can be used to enable experimental features. These features
   // provide no guarantees.
   enable: { type: "string[]" },