fix(expo, ios): expo plugin added import multiple times

[DoctorJohn]

Description

This PR fixes a regression introduced in #6223 and reported in #6477.

Related issues

Fixes #6477

Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
  • Yes
• My change supports the following platforms;
  • Android
  • iOS
• My change includes tests;
  • e2e tests added or updated in packages/\*\*/e2e
  • jest tests added or updated in packages/\*\*/__tests__
• I have updated TypeScript types that are affected by my change.
• This is a breaking change;
  • Yes
  • No

Test Plan

I added a test that fails without the changes and succeeds with them :)

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Name	Status	Preview	Updated
react-native-firebase	✅ Ready (Inspect)	Visit Preview	Sep 3, 2022 at 4:03PM (UTC)

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Name	Status	Preview	Updated
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[codecov]

Codecov Report

Merging #6507 (9a3a897) into main (a05f63d) will increase coverage by 0.03%.
The diff coverage is 100.00%.

❗ Current head 9a3a897 differs from pull request most recent head d58fce2. Consider uploading reports for the commit d58fce2 to get more accurate results

@@            Coverage Diff             @@
##             main    #6507      +/-   ##
==========================================
+ Coverage   72.30%   72.33%   +0.03%     
==========================================
  Files         109      109              
  Lines        4657     4657              
  Branches     1048     1048              
==========================================
+ Hits         3367     3368       +1     
+ Misses       1212     1211       -1     
  Partials       78       78              

[mikehardy]

This looks great, and a test! Bestill my heart ❤️ 😆
Thank you @DoctorJohn