missing --entry-point example in docs

[edublancas]

see #1085 for context

[Bhardwaj-Himanshu]

Hi @edublancas, after looking into this issue and diving from one # to another! Realised the last PR raised for this issue, was closed due to inactivity!
Could I raise a PR to the same, and fix it up?
Also, I am very new to the org. so am currently tinkering with the documentation, but will keep you updated through!

[edublancas]

sure, feel free to open a PR!

[Bhardwaj-Himanshu]

Hi again @edublancas, after researching the paragraph and usage for --entry-point is already present in the file from lines-
https://github.com/ploomber/ploomber/blob/master/doc/api/cli.rst#default-locations(lines 390-430)

Should we add more to it? or move it upwards? Cause creating another section for the same won't make sense!