Extracted getBackupFilePath out of route settings module

refs https://linear.app/tryghost/issue/CORE-35/refactor-route-and-redirect-settings
refs e457fd5fe0 (diff-b292e8480eee007786cc602f55ed05006a06b8da9fe6934d51fbef8328013278R36)

- The method is used in a similar fassion in redirects modules, so should be a gret target for extraction and reuse.
- Bonuses: we drop 'path' and 'moment-timezone' dependencies from route settings module!

core/server/services/route-settings/route-settings.js

@@ -1,7 +1,5 @@
 const Promise = require('bluebird');
-const moment = require('moment-timezone');
 const fs = require('fs-extra');
-const path = require('path');
 const crypto = require('crypto');
 const urlService = require('../url');
 
@@ -43,11 +41,6 @@ const messages = {
 const filename = 'routes';
 const ext = 'yaml';
 
-const getBackupFilePath = () => {
-    const settingsFolder = config.getContentPath('settings');
-    return path.join(settingsFolder, `${filename}-${moment().format('YYYY-MM-DD-HH-mm-ss')}.${ext}`);
-};
-
 const createBackupFile = async (settingsPath, backupPath) => {
     return await fs.copy(settingsPath, backupPath);
 };
@@ -79,7 +72,7 @@ const readFile = (settingsFilePath) => {
 
 const setFromFilePath = async (filePath) => {
     const settingsPath = settingsPathManager.getDefaultFilePath();
-    const backupPath = getBackupFilePath();
+    const backupPath = settingsPathManager.getBackupFilePath();
 
     await createBackupFile(settingsPath, backupPath);
     await saveFile(filePath, settingsPath);

yarn.lock

@@ -3979,9 +3979,9 @@ data-urls@^3.0.1:
     whatwg-url "^10.0.0"
 
 date-fns@^2.24.0:
-  version "2.26.0"
-  resolved "https://registry.yarnpkg.com/date-fns/-/date-fns-2.26.0.tgz#fa45305543c392c4f914e50775fd2a4461e60fbd"
-  integrity sha512-VQI812dRi3cusdY/fhoBKvc6l2W8BPWU1FNVnFH9Nttjx4AFBRzfSVb/Eyc7jBT6e9sg1XtAGsYpBQ6c/jygbg==
+  version "2.24.0"
+  resolved "https://registry.yarnpkg.com/date-fns/-/date-fns-2.24.0.tgz#7d86dc0d93c87b76b63d213b4413337cfd1c105d"
+  integrity sha512-6ujwvwgPID6zbI0o7UbURi2vlLDR9uP26+tW6Lg+Ji3w7dd0i3DOcjcClLjLPranT60SSEFBwdSyYwn/ZkPIuw==
 
 dateformat@~3.0.3:
   version "3.0.3"