[DRE-maint] Bug#1025220: passenger: Passenger startup fails with nodejs applications using node versions later than 14.x

[Cool Fire]

Some additional digging findings;

- Testing and Unstable packages are not affected as they are built from 
the upstream passenger 6.x branch, which already includes this fix.
- Stable package is not affected when using the nodejs package from 
debian stable repo as this is still on the nodejs 12.x branch.
- Stable package is affected when using newer stable release from 
upstream vendor repo (deb.nodesource.com).

It would be superb if we could get the fix from passenger 6.x backported 
to the debian stable passenger package so we can deploy on modern nodejs 
versions.