Make FactorioServer.exampleSettings static

Convert the exampleSettings method to be a static method.

lib/factorio/server.js

@@ -753,10 +753,11 @@ class FactorioServer extends events.EventEmitter {
 	 *
 	 * Loads server-settings.example.json from the data dir.
 	 *
+	 * @param {string} dataDir - The data directory for Factorio
 	 * @returns {object} the parsed server-settings.
 	 */
-	async exampleSettings() {
-		return JSON.parse(await fs.readFile(this.dataPath("server-settings.example.json"), "utf-8"));
+	static async exampleSettings(dataDir) {
+		return JSON.parse(await fs.readFile(path.join(dataDir, "server-settings.example.json"), "utf-8"));
 	}
 
 	async _writeConfigIni() {