chore: upgrade to ESLint v9

Author: robertrossmann

eslint.config.mjs

@@ -1,4 +1,4 @@
-import nodev20 from '@strv/eslint-config-node/v20'
+import node from '@strv/eslint-config-node'
 import nodeopt from '@strv/eslint-config-node/optional'
 import nodestyle from '@strv/eslint-config-node/style'
 import ts from '@strv/eslint-config-typescript'
@@ -12,13 +12,13 @@ const globs = {
   tests: '**/*.test.ts',
 }
 
-/** @type {Array<import("eslint").Linter.FlatConfig>} */
+/** @type {Array<import("eslint").Linter.Config>} */
 const config = [
   { linterOptions: {
     reportUnusedDisableDirectives: true,
   } },
   { ignores: ['**/*.js', '**/*.d.ts', 'node_modules'] },
-  { files: [globs.ts, globs.mjs], ...nodev20 },
+  { files: [globs.ts, globs.mjs], ...node },
   { files: [globs.ts, globs.mjs], ...nodeopt },
   { files: [globs.ts, globs.mjs], ...nodestyle },
 
@@ -27,12 +27,6 @@ const config = [
   { files: [globs.ts], ...tsstyle },
 
   { files: [globs.tests], ...mocha },
-
-  // Any custom settings to be applied
-  { files: [globs.ts],
-    languageOptions: {
-      parserOptions: { project: './tsconfig.json' },
-    } },
 ]
 
 export default config