Replace deprecated tseslint.config() with defineConfig() (#37926)

- https://typescript-eslint.io/packages/typescript-eslint/#migrating-to-defineconfig

Author: mikeharder

.github/eslint.config.js

@@ -1,8 +1,9 @@
 import eslint from "@eslint/js";
+import { defineConfig } from "eslint/config";
 import globals from "globals";
 import tseslint from "typescript-eslint";
 
 /** @type {import('eslint').Linter.Config[]} */
-export default tseslint.config(eslint.configs.recommended, tseslint.configs.recommended, {
+export default defineConfig(eslint.configs.recommended, tseslint.configs.recommended, {
   languageOptions: { globals: globals.node },
 });

eng/tools/spec-gen-sdk-runner/eslint.config.js

@@ -7,9 +7,10 @@
 
 import eslint from "@eslint/js";
 import eslintPluginUnicorn from "eslint-plugin-unicorn";
+import { defineConfig } from "eslint/config";
 import tseslint from "typescript-eslint";
 
-const config = tseslint.config(
+const config = defineConfig(
   // ========================================
   // ESLint + TS-ESLint configs
   // ========================================