ERROR: Can not read `EnvironmentFile` No such file or directory

[ShreyasMahangade]

When created custom postgres service unit file with below extra line in unit file:

EnvironmentFile=-/path/to/env

Enable the custom unit and initialize DB:

# /usr/bin/systemctl enable custom-pg.service
# postgresql-setup --initdb --unit custom-pg --port 3333
ERROR: Can not read EnvironmentFile 'EnvironmentFiles=/path/to/env' specified
        in custom-pg.service
/usr/bin/postgresql-setup: line 415: EnvironmentFiles=/path/to/env: No such file or directory

Note: Line number 415 because this was reproduced on RHEL system not on upstream scripts.