fix(dynamic_links,ios): retry handling iOS universal link on network failure

[jherencia]

Description

People have posted some issues:

• [firebase_dynamic_links] Not working on app start #100
• [firebase_dynamic_links] plugin is not working in ios when app is in Back ground. #33
  on iOS dynamic links behavior. All of this use cases worked before iOS 12 release so I assume Firebase update and iOS 12 have changed things.

I've based my work on the release of rn-firebase 6.0 that had the same problems and were fixed so this PR takes some ideas from them.

Related Issues

• Fixes [firebase_dynamic_links] Not working on app start #100
• Fixes [firebase_dynamic_links] plugin is not working in ios when app is in Back ground. #33

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[jherencia]

@Salakar

This is a clone of #255 with the code updated to be mergeable.

[himsa]

Any update on this? @Salakar
I see the newest version is 0.7.0+1
is this PR merged ?

[b-jan]

Hello @Salakar and @jherencia
Can we merge this one soon?

[josh-burton]

I've tested this PR and I'm unable to get a link passed through from the app store to work, unless I add a few seconds delay before checking for pending links.