Fix linking manager library name in documentation

[vedadsose]

I had an issue while using

#import "RCTLinkingManager.h"

But when replaced with

#import <React/RCTLinkingManager.h>

the build succeeds.

Looks fine on the website:

[facebook-github-bot]

Thank you for your pull request and welcome to our community. We require contributors to sign our Contributor License Agreement, and we don't seem to have you on file. In order for us to review and merge your code, please sign up at https://code.facebook.com/cla - and if you have received this in error or have any questions, please drop us a line at cla@fb.com. Thanks!

If you are contributing on behalf of someone else (eg your employer): the individual CLA is not sufficient - use https://developers.facebook.com/opensource/cla?type=company instead. Contact cla@fb.com if you have any questions.

[harunsmrkovic]

👍

[facebook-github-bot]

Thank you for signing our Contributor License Agreement. We can now accept your code for this (and any) Facebook open source project. Thanks!

[ericvicenti]

@facebook-github-bot shipit-ninja

[facebook-github-bot]

@ericvicenti has imported this pull request. If you are a Facebook employee, you can view this diff on Phabricator.