startOrRestart fails when given a plain script

What's going wrong?

startOrRestart fails when given a plain script.

How could we reproduce this issue?

$ touch /tmp/dummy.js
$ pm2 startOrRestart /tmp/dummy.js
/usr/lib/node_modules/pm2/lib/API.js:948
    if (config.deploy)
               ^

TypeError: Cannot read property 'deploy' of undefined
    at API._startJson (/usr/lib/node_modules/pm2/lib/API.js:948:16)
    at Command.<anonymous> (/usr/lib/node_modules/pm2/lib/binaries/CLI.js:321:9)
    at Command.listener (/usr/lib/node_modules/pm2/node_modules/commander/index.js:315:8)
    at Command.emit (events.js:315:20)
    at Command.parseArgs (/usr/lib/node_modules/pm2/node_modules/commander/index.js:651:12)
    at Command.parse (/usr/lib/node_modules/pm2/node_modules/commander/index.js:474:21)
    at beginCommandProcessing (/usr/lib/node_modules/pm2/lib/binaries/CLI.js:147:13)
    at /usr/lib/node_modules/pm2/lib/binaries/CLI.js:221:7
    at /usr/lib/node_modules/pm2/lib/API.js:182:16
    at /usr/lib/node_modules/pm2/lib/Client.js:54:16

Supporting information

--- PM2 report ----------------------------------------------------------------
Date                 : Tue Mar 16 2021 19:50:18 GMT+0000 (Coordinated Universal Time)
===============================================================================
--- Daemon -------------------------------------------------
pm2d version         : 4.5.5
node version         : 14.16.0
node path            : /usr/bin/pm2
argv                 : /usr/bin/node,/usr/lib/node_modules/pm2/lib/Daemon.js
argv0                : node
user                 : app
uid                  : 1000
gid                  : 1000
uptime               : 157min
===============================================================================
--- CLI ----------------------------------------------------
local pm2            : 4.5.5
node version         : 14.16.0
node path            : /usr/bin/pm2
argv                 : /usr/bin/node,/usr/bin/pm2,report
argv0                : node
user                 : app
uid                  : 1000
gid                  : 1000
===============================================================================
--- System info --------------------------------------------
arch                 : x64
platform             : linux
type                 : Linux
cpus                 : Intel(R) Xeon(R) Gold 6140 CPU @ 2.30GHz
cpus nb              : 1
freemem              : 181379072
totalmem             : 1029009408
home                 : /home/app
===============================================================================
--- PM2 list -----------------------------------------------
┌─────┬───────────┬─────────────┬─────────┬─────────┬──────────┬────────┬──────┬───────────┬──────────┬──────────┬──────────┬──────────┐
│ id  │ name      │ namespace   │ version │ mode    │ pid      │ uptime │ ↺    │ status    │ cpu      │ mem      │ user     │ watching │
└─────┴───────────┴─────────────┴─────────┴─────────┴──────────┴────────┴──────┴───────────┴──────────┴──────────┴──────────┴──────────┘
Current process list running is not in sync with saved list. App app app differs. Type 'pm2 save' to synchronize.
===============================================================================
--- Daemon logs --------------------------------------------
/home/app/.pm2/pm2.log last 20 lines:
PM2        | 2021-03-16T19:36:32: PM2 log: App [app:2] online
PM2        | 2021-03-16T19:36:33: PM2 log: App [app:2] exited with code [1] via signal [SIGINT]
PM2        | 2021-03-16T19:36:33: PM2 log: App [app:2] starting in -fork mode-
PM2        | 2021-03-16T19:36:33: PM2 log: App [app:2] online
PM2        | 2021-03-16T19:36:33: PM2 log: App [app:2] exited with code [1] via signal [SIGINT]
PM2        | 2021-03-16T19:36:33: PM2 log: App [app:2] starting in -fork mode-
PM2        | 2021-03-16T19:36:33: PM2 log: App [app:2] online
PM2        | 2021-03-16T19:36:34: PM2 log: App [app:2] exited with code [1] via signal [SIGINT]
PM2        | 2021-03-16T19:36:34: PM2 log: App [app:2] starting in -fork mode-
PM2        | 2021-03-16T19:36:34: PM2 log: App [app:2] online
PM2        | 2021-03-16T19:36:35: PM2 log: App [app:2] exited with code [1] via signal [SIGINT]
PM2        | 2021-03-16T19:36:35: PM2 log: App [app:2] starting in -fork mode-
PM2        | 2021-03-16T19:36:35: PM2 log: App [app:2] online
PM2        | 2021-03-16T19:36:35: PM2 log: App [app:2] exited with code [1] via signal [SIGINT]
PM2        | 2021-03-16T19:36:35: PM2 log: Script /home/app/app/build/src/index.js had too many unstable restarts (16). Stopped. "errored"
PM2        | 2021-03-16T19:50:11: PM2 log: Stopping app:app id:1
PM2        | 2021-03-16T19:50:11: PM2 log: Stopping app:app id:2
PM2        | 2021-03-16T19:50:11: PM2 error: app=app id=2 does not have a pid
PM2        | 2021-03-16T19:50:11: PM2 log: App [app:1] exited with code [0] via signal [SIGINT]
PM2        | 2021-03-16T19:50:11: PM2 log: pid=365025 msg=process killed

Start with lib/API.js around line 948 and the CLI entry in lib/binaries/CLI.js around line 321. Reproduce the failure using the reported touch and pm2 startOrRestart commands, then trace how the plain script reaches _startJson. Done means the command no longer throws the reported TypeError for a plain script.