Fix the broken iOS OSS job

Summary:
Fixes the iOS OSS job which was failing. The root cause of the problem is as follows:

- RSocket was referring the master branch of rsocket/rsocket-cpp, fixed it by forking it and making its own release, unfortunately they don't make a release.
- Folly referred to the January's release. The current master branch of RSocket doesn't build with the latest release of the Folly, [this commit](b51dc569eb) is responsible for the breakage. Thus I made a Rsocket release, right before this [commit](b51dc569eb), so that it builds.Although, the current master branch of Folly builds with the current master branch of rsocket, but we will have to wait on Folly team to make a release. Once they do that I will update bit RSocket and Folly releases.

Reviewed By: jknoxville

Differential Revision: D14668686

fbshipit-source-id: 6b0362632c26355a69a3f33a031b71c88e7dd45b

iOS/Podspecs/Flipper-Folly.podspec

@@ -1,12 +1,12 @@
 Pod::Spec.new do |spec|
   spec.name = 'Flipper-Folly'
-  spec.version = '1.2.0'
+  spec.version = '1.3.0'
   spec.license = { :type => 'Apache License, Version 2.0' }
   spec.homepage = 'https://github.com/facebook/folly'
   spec.summary = 'An open-source C++ library developed and used at Facebook.'
   spec.authors = 'Facebook'
   spec.source = { :git => 'https://github.com/facebook/folly.git',
-                  :tag => "v2019.01.14.00"}
+                  :tag => "v2019.03.25.00"}
   spec.module_name = 'folly'
   spec.dependency 'boost-for-react-native'
   spec.dependency 'DoubleConversion'