Change doc link to point to AnimatedValueXY
Change doc link to point to AnimatedValueXY

Summary:
Currently goes to the same page

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Online doc was not helpful because the link kept going to the wrong page. Someone told me to make a pull request

Documentation change
Go to original link https://facebook.github.io/react-native/docs/animated.html#animatedvaluexy
See that it does not have any info on valuexy

Go to https://facebook.github.io/react-native/releases/next/docs/animatedvaluexy.html
See that the page loads and has information about valuexy

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Help reviewers and the release process by writing your own release notes

**INTERNAL and MINOR tagged notes will not be included in the next version's final release notes.**

  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 https://github.com/facebook/react-native/pull/16999

Differential Revision: D6467512

Pulled By: shergin

fbshipit-source-id: 69887e34446c3ea57ad831ed870be4e1a8a7a514

facebook/react-native,exponent/react-native,rickbeerendonk/react-native,hammerandchisel/react-native,janicduplessis/react-native,arthuralee/react-native,pandiaraj44/react-native,rickbeerendonk/react-native,hoangpham95/react-native,facebook/react-native,facebook/react-native,rickbeerendonk/react-native,hammerandchisel/react-native,rickbeerendonk/react-native,Bhullnatik/react-native,exponent/react-native,exponent/react-native,hoangpham95/react-native,Bhullnatik/react-native,pandiaraj44/react-native,facebook/react-native,rickbeerendonk/react-native,myntra/react-native,rickbeerendonk/react-native,dikaiosune/react-native,myntra/react-native,facebook/react-native,hoangpham95/react-native,hammerandchisel/react-native,exponentjs/react-native,ptmt/react-native-macos,javache/react-native,hoastoolshop/react-native,hoastoolshop/react-native,jevakallio/react-native,hoangpham95/react-native,exponentjs/react-native,janicduplessis/react-native,arthuralee/react-native,javache/react-native,pandiaraj44/react-native,ptmt/react-native-macos,javache/react-native,hammerandchisel/react-native,jevakallio/react-native,Bhullnatik/react-native,pandiaraj44/react-native,ptmt/react-native-macos,myntra/react-native,ptmt/react-native-macos,janicduplessis/react-native,javache/react-native,dikaiosune/react-native,janicduplessis/react-native,hoastoolshop/react-native,hoangpham95/react-native,dikaiosune/react-native,exponentjs/react-native,rickbeerendonk/react-native,myntra/react-native,myntra/react-native,exponentjs/react-native,pandiaraj44/react-native,jevakallio/react-native,jevakallio/react-native,hammerandchisel/react-native,hammerandchisel/react-native,hoangpham95/react-native,janicduplessis/react-native,janicduplessis/react-native,ptmt/react-native-macos,jevakallio/react-native,myntra/react-native,javache/react-native,hoastoolshop/react-native,pandiaraj44/react-native,janicduplessis/react-native,dikaiosune/react-native,Bhullnatik/react-native,hoastoolshop/react-native,dikaiosune/react-native,arthuralee/react-native,pandiaraj44/react-native,javache/react-native,exponentjs/react-native,hoangpham95/react-native,exponent/react-native,javache/react-native,dikaiosune/react-native,exponent/react-native,jevakallio/react-native,arthuralee/react-native,exponent/react-native,exponent/react-native,Bhullnatik/react-native,javache/react-native,exponent/react-native,facebook/react-native,hammerandchisel/react-native,exponentjs/react-native,facebook/react-native,facebook/react-native,ptmt/react-native-macos,exponentjs/react-native,hoastoolshop/react-native,myntra/react-native,facebook/react-native,jevakallio/react-native,dikaiosune/react-native,exponentjs/react-native,jevakallio/react-native,rickbeerendonk/react-native,hoastoolshop/react-native,hoangpham95/react-native,Bhullnatik/react-native,jevakallio/react-native,myntra/react-native,rickbeerendonk/react-native,Bhullnatik/react-native,javache/react-native,hammerandchisel/react-native,pandiaraj44/react-native,arthuralee/react-native,ptmt/react-native-macos,hoastoolshop/react-native,Bhullnatik/react-native,ptmt/react-native-macos,janicduplessis/react-native,dikaiosune/react-native,myntra/react-native