Removed broken link for 'Getting Help' in the README

Summary:
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I was going through the README and came across a broken link, so I needed to fix it.

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[ DOCS     ]   [ BROKEN LINK ]   [README.md]
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  CATEGORY
[----------]        TYPE
[ CLI      ]   [-------------]      LOCATION
[ DOCS     ]   [ BREAKING    ]   [-------------]
[ GENERAL  ]   [ BUGFIX      ]   [-{Component}-]
[ INTERNAL ]   [ ENHANCEMENT ]   [ {File}      ]
[ IOS      ]   [ FEATURE     ]   [ {Directory} ]   |-----------|
[ ANDROID  ]   [ MINOR       ]   [ {Framework} ] - | {Message} |
[----------]   [-------------]   [-------------]   |-----------|

[CATEGORY] [TYPE] [LOCATION] - MESSAGE

 EXAMPLES:

 [IOS] [BREAKING] [FlatList] - Change a thing that breaks other things
 [ANDROID] [BUGFIX] [TextInput] - Did a thing to TextInput
 [CLI] [FEATURE] [local-cli/info/info.js] - CLI easier to do things with
 [DOCS] [BUGFIX] [GettingStarted.md] - Accidentally a thing/word
 [GENERAL] [ENHANCEMENT] [Yoga] - Added new yoga thing/position
 [INTERNAL] [FEATURE] [./scripts] - Added thing to script that nobody will see
-->
Closes #17620

Differential Revision: D6727943

Pulled By: hramos

fbshipit-source-id: ef76d1e4847bc9b190a2076d64fa89a86ca9df93

Author: rickydam

README.md

@@ -14,7 +14,6 @@ See the official [React Native website](https://facebook.github.io/react-native/
 Supported operating systems are >= Android 4.1 (API 16) and >= iOS 8.0.
 
 - [Getting Started](#getting-started)
-- [Getting Help](#getting-help)
 - [Documentation](#documentation)
 - [Upgrading](#upgrading)
 - [Contributing](#contributing)