fix: proper type for isRequired in health check schema (#1367)

Author: acoates-ms

packages/cli/src/tools/config/schema.ts

@@ -39,7 +39,7 @@ const healthCheck = t.object({
   healthchecks: t.array().items(
     t.object({
       label: t.string().required(),
-      isRequired: t.string(),
+      isRequired: t.bool(),
       description: t.string(),
       getDiagnostics: t.func(),
       win32AutomaticFix: t.func(),