CLI doc correction on npm-init.md

[Peallyz]

Resolving the issue #5837 for repo :
https://github.com/npm/[cli] (https://github.com/npm/cli)

Missing backticks on "npm init (same as `npx )" line 25 for both files (v8 and v9)

Despite what it said on CONTRIBUTION.md, this issue can't be done on npm/cli cause of autogenerated code.

Hope I did well, do not hesitate to tell me if i did wrong.
I'll ask to close the associated issu if it's good for you.

References

content/cli/v8/commands/npm-init.md
content/cli/v9/commands/npm-init.md
Line 25 added missing backticks
Line 28 "innit" -> "init"

[lukekarrys]

this fix for this issue would need to be made in the npm/cli repo. see my comment here for more info: npm/cli#5837 (comment)

also the command innit is not a typo, but allows for the command to be typed both ways and still be run as init.