updatenotification: update_helper.js recode with pm2 library (v2.27.x) (#3332)

#3285

Because there is so many conflit with package,
I have rewrite the code with v2.27.0-develop

For remember:

 * recode: `update_helper.js` with `pm2` library
 * fix: default config -> `updates` is a array
 * delete: `command-exists` library (not used)
 * delete: `PM2_GetList()`  function (not used)
 * add: check `updates.length` (prevent crash)
 * add: `[PM2]` tag in log (for better visibility)
 * add: `pm2` library
 
advantage:
  * we use the pm2 library directly
* avoids weird returns from child_process.exec when requesting a json
format from pm2
  * simplified the code

inconvenient:
  * we have vulnerabilities with axios

240120 Fix:
* use `pm2_env.pm_cwd` instead of `pm2_env.PWD` : prevent using `pm2
restart <id> --update-env` in other directory (for enable GPU rendering
for exemple)
 * resolve packages (again)

package.json

@@ -72,7 +72,6 @@
 	},
 	"dependencies": {
 		"ansis": "^2.0.3",
-		"command-exists": "^1.2.9",
 		"console-stamp": "^3.1.2",
 		"envsub": "^4.1.0",
 		"eslint": "^8.56.0",
@@ -85,6 +84,7 @@
 		"module-alias": "^2.2.3",
 		"moment": "^2.30.1",
 		"node-ical": "^0.17.1",
+		"pm2": "^5.3.0",
 		"socket.io": "^4.7.4",
 		"systeminformation": "^5.21.22"
 	},