fix: remove explicit folly version (#3416)

## Description

As a version of folly can change between versions of React-native we need to remove an explicit version of `folly_version` from our libraries to let RN infer the correct version.

Change based on th3rdwave/react-native-safe-area-context@eb111ff

## Changes

Removed explicit folly version from RNReanimated.podspec

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## Test code and steps to reproduce

Build FabricExample/

## Checklist

- [ ] Ensured that CI passes

RNReanimated.podspec

@@ -54,7 +54,6 @@ end
 
 folly_flags = '-DFOLLY_NO_CONFIG -DFOLLY_MOBILE=1 -DFOLLY_USE_LIBCPP=1 -Wno-comma -Wno-shorten-64-to-32 -DRNVERSION=' + rnVersion
 folly_compiler_flags = folly_flags + ' ' + '-Wno-comma -Wno-shorten-64-to-32'
-folly_version = '2021.06.28.00-v2'
 boost_compiler_flags = '-Wno-documentation'
 fabric_flags = ''
 if fabric_enabled
@@ -101,7 +100,7 @@ Pod::Spec.new do |s|
   if fabric_enabled
     s.dependency "React-RCTFabric"
     s.dependency "React-Codegen"
-    s.dependency "RCT-Folly", folly_version
+    s.dependency "RCT-Folly"
   else
     s.dependency "#{folly_prefix}Folly"
   end