coafile.rst: Fix bad setting example codeblock markup

[co-robo]

difficulty/newcomer
Opened by @mamat-rahmat at Gitter

[0x48piraj]

I want to do it!

BTW, @co-robo Are you talking about :

#bad! setting1 = 1
[section1] # setting1 is inherited setting2 = 2

[mamat-rahmat]

Yes, exactly

[0x48piraj]

Got it 😎

[Makman2]

Unassigning due to inactivity.

[mrsaicharan1]

@co-robo Can I work on this issue?

[pavankrishna13]

I want to work on this issue. Can I get assigned?

[Makman2]

You both already have newcomer issues assigned, so please continue with a difficulty/low one ;)

[Naveenaidu]

I want to work on this issue. Can i get assigned to it?