plugin-management: Move code to ESM module

plugins/headlamp-plugin/plugin-management/plugin-management.js → plugins/headlamp-plugin/plugin-management/plugin-management.mjs

@@ -1,21 +1,21 @@
 /**
- * plugin-management-utils.js has the core logic for managing plugins in Headlamp.
+ * plugin-management.mjs has the core logic for managing plugins in Headlamp.
  *
  * Provides methods for installing, updating, listing and uninstalling plugins.
  *
  * Used by:
  * - plugins/headlamp-plugin/bin/headlamp-plugin.js cli
  * - app/ to manage plugins.
  */
-const fs = require('fs');
-const os = require('os');
-const zlib = require('zlib');
-const tar = require('tar');
-const path = require('path');
-const crypto = require('crypto');
-const stream = require('stream');
-const semver = require('semver');
-const envPaths = require('env-paths');
+import fs from 'fs';
+import os from 'os';
+import zlib from 'zlib';
+import tar from 'tar';
+import path from 'path';
+import crypto from 'crypto';
+import stream from 'stream';
+import semver from 'semver';
+import envPaths from 'env-paths';
 
 // comment out for testing
 // function sleep(ms) {