Update Starscream.podspec

[uypanha]

Fixed Xcode 12 iOS minimum version support

[acmacalister]

thanks. We went ahead and updated it today.

[pabiagioli]

you missed updating the spec.version field
I'm having issues since 4.0.5 like this

dyld[799]: Symbol not found: _$s10Starscream17WebSocketDelegateP10didReceive5event6clientyAA0bC5EventO_AA0bC0CtFTq

Did you modify the WebSocketDelegate signatures? maybe the podspec version field is related to this error

I'm using the pod like this

pod 'Starscream', '~> 4.0.0'

it has been solved when changing the line like this

pod 'Starscream', :git => 'git@github.com:daltoniam/Starscream.git', :tag => '4.0.4', :submodules => true

versions 4.0.5 and 4.0.6 say I'm installing 4.0.4