Add Nodemon usage instructions for live server restarting

[Melkzedk]

Added instructions for using Nodemon to restart the Node.js server automatically during development.

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🚦 Lighthouse Results (Mobile & Desktop)

URL	Device	Perf	A11y	Best Practices
/	mobile	🔴 53	🟢 100	🟢 96
/en/blog/posts.html	mobile	🔴 73	🟢 96	🟢 96
/en/5x/api.html	mobile	🟠 75	🟢 95	🟢 96
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/en/blog/posts.html	desktop	🟢 100	🟢 96	🟢 92
/en/5x/api.html	desktop	🟢 99	🟢 95	🟢 96

[efekrskl]

Thanks for the PR!

Unfortunately, I see several issues with the PR and I don't think it'd be a good contribution. Just to name a few:

1. I don't understand how is this relevant to express-generator docs (at best, it'd be a different section in docs)
2. Now that node --watch is stable, this might be favored (although, I might be wrong, not sure if they map 1:1)
3. Your example doesn't even work, as the main entry file is not server.js with express-generator (as shown in the docs)

[ShubhamOulkar]

agreed with @efekrskl

[bjohansebas]

i agree with the others, i'm going to close