[image_picker] Updates example app Android compileSdkVersion to 33.

[bparrishMines]

Pre-launch Checklist

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• I listed at least one issue that this PR fixes in the description above.
• I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy, or this PR is exempt from version changes.
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[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption to this rule, contact Hixie on the #hackers channel in Chat (don't just cc him here, he won't see it! He's on Discord!).

If you are not sure if you need tests, consider this rule of thumb: the purpose of a test is to make sure someone doesn't accidentally revert the fix. Ask yourself, is there anything in your PR that you feel it is important we not accidentally revert back to how it was before your fix?

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[reidbaker]

This change happens in #3271 I think.

[bparrishMines]

I can close this in favor of #3271. I just created this because its blocking the roll from Flutter and I wasn't sure sure when it would land.