Added #ifdef UNITY_IOS

[wmcburnett-HB]

A quick fix for issue #508.

Added #ifdef UNITY_IOS for the two build files in the IOS project so that a CI builder like game.ci can build Android in environments without the iOS modules.

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This change is 

[Bald1nh0]

I need this PR :)

[episuarez]

Is there a deadline to apply this PR?

[Bald1nh0]

No, but we use game.ci build scheme, and android builds crashes, so we need to use another build machine.

[wmcburnett-HB]

Well, I can't assign reviewers. @gdeglin ?

[shepherd-l]

com.onesignal.unity.ios/Editor/BuildPostProcessor.cs line 1 at r1 (raw file):

#if UNITY_IOS

Just a nit but, could you place this line after the “Modified MIT License” and “Testing Notes”?

[shepherd-l]

com.onesignal.unity.ios/Editor/PBXProjectExtensions.cs line 1 at r1 (raw file):

#if UNITY_IOS

Another nit, could you place this line after the MIT License?

[shepherd-l]

Thanks for making a PR. Could you also open this against the develop branch instead and update the CHANGELOG with your change?

CHANGELOG.md Example:

## [Unreleased]
### [Fixed]

- <Your change>

[stopiccot]

#556 This PR can be closed now

[shepherd-l]

Added this in the 3.0.6 release with #556