Fixed "constants" typo
Fixed "constants" typo

Summary:
<!--
Thank you for sending the PR! We appreciate you spending the time to work on these changes.

Help us understand your motivation by explaining why you decided to make this change.

You can learn more about contributing to React Native here: http://facebook.github.io/react-native/docs/contributing.html

Happy contributing!

-->

oss-typos DC workshop: rid the world of typos.

Manual spell checker reporting duty.

<!--
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
-->

[DOCS][MINOR][JSTimers.js] Fixed "constants" typo
Closes https://github.com/facebook/react-native/pull/16559

Differential Revision: D6184938

Pulled By: shergin

fbshipit-source-id: d16822d3885c6439239102df2790f5dbf5271a19

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