Upgrade typescript config to target NodeJS 20

Fixes the error:

```
src/parsers/dart-json/dart-json-parser.ts:209:123 - error TS1501: This regular expression flag is only available when targeting 'es2018' or later.

209         /^══╡ EXCEPTION CAUGHT BY FLUTTER TEST FRAMEWORK ╞═+\s+(.*)\s+When the exception was thrown, this was the stack:/ms
```

package.json

@@ -77,5 +77,8 @@
     "suiteNameTemplate": "{filepath}",
     "classNameTemplate": "{classname}",
     "titleTemplate": "{title}"
+  },
+  "engines": {
+    "node": ">=20"
   }
 }

tsconfig.json

@@ -1,12 +1,16 @@
 {
   "compilerOptions": {
-    "target": "es6",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
-    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
-    "outDir": "./lib",                        /* Redirect output structure to the directory. */
-    "rootDir": "./src",                       /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
-    "strict": true,                           /* Enable all strict type-checking options. */
-    "noImplicitAny": true,                    /* Raise error on expressions and declarations with an implied 'any' type. */
-    "esModuleInterop": true                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
+    "lib": ["es2023"],
+    "module": "node16",
+    "target": "es2022",
+
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "moduleResolution": "node16",
+
+    "outDir": "./lib",
+    "rootDir": "./src",
   },
   "exclude": ["node_modules", "**/*.test.ts"]
 }