[image_picker] updated VALID_ARCHS to support iPhone simulator

[jlalvarez18]

Description

Currently the Image Picker plugin no longer works on Xcode 11.4.1 in the iPhone simulator. I updated the podspec to set the VALID_ARCHS to match other plugins in this project.

Related Issues

Fixes flutter/flutter#51395

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[jlalvarez18]

@googlebot I signed it!

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[jlalvarez18]

I will wait until reviewed to update the CHANGEDLOG and Pubspec version until approved to avoid all the merge conflicts :)

[jlubeck]

Any thoughts on well this will be merged?

[Nash0x7E2]

cc: @cyanglaz

[jmagman]

This looks good, thank you for making this change!
The pubspec and CHANGELOG need to be updated, then we'll merge and publish. I can also do this and push to your fork, if you prefer (I know you worked on this more than a month ago).
\cc @cyanglaz

[jmagman]

Took the liberty of pushing the CHANGELOG, pubspec version bump, and AUTHORS to add @jlalvarez18.

[cyanglaz]

LGTM! Added a line between the version number and the message in CHANGELOG.md