Use node prefix for build-in modules (#3340)

It is basically a cosmetic thing, but has the following advantages:

1. Consistency with the official node documentation. The prefix is used
there.
2. It is easier to recognize the build-in modules.

tests/e2e/fonts_spec.js

@@ -3,7 +3,7 @@ const helpers = require("./helpers/global-setup");
 describe("All font files from roboto.css should be downloadable", () => {
 	const fontFiles = [];
 	// Statements below filters out all 'url' lines in the CSS file
-	const fileContent = require("fs").readFileSync(`${__dirname}/../../fonts/roboto.css`, "utf8");
+	const fileContent = require("node:fs").readFileSync(`${__dirname}/../../fonts/roboto.css`, "utf8");
 	const regex = /\burl\(['"]([^'"]+)['"]\)/g;
 	let match = regex.exec(fileContent);
 	while (match !== null) {

tests/e2e/helpers/basic-auth.js

@@ -1,4 +1,4 @@
-const path = require("path");
+const path = require("node:path");
 const auth = require("express-basic-auth");
 const express = require("express");
 

tests/e2e/serveronly_spec.js

@@ -6,7 +6,7 @@ describe("App environment", () => {
 	let serverProcess;
 	beforeAll(async () => {
 		process.env.MM_CONFIG_FILE = "tests/configs/default.js";
-		serverProcess = await require("child_process").spawn("npm", ["run", "server"], { env: process.env, detached: true });
+		serverProcess = await require("node:child_process").spawn("npm", ["run", "server"], { env: process.env, detached: true });
 		// we have to wait until the server is startet
 		await delay(2000);
 	});

tests/e2e/template_spec.js

@@ -1,4 +1,4 @@
-const fs = require("fs");
+const fs = require("node:fs");
 const helpers = require("./helpers/global-setup");
 
 describe("templated config with port variable", () => {

tests/e2e/translations_spec.js

@@ -1,5 +1,5 @@
-const fs = require("fs");
-const path = require("path");
+const fs = require("node:fs");
+const path = require("node:path");
 const helmet = require("helmet");
 const { JSDOM } = require("jsdom");
 const express = require("express");