Proposed changes

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If it fixes a bug or resolves a feature request, be sure to link to that issue.

Types of changes

What types of changes does your code introduce to tipsi-stripe?
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• [x ] Bugfix (a non-breaking change which fixes an issue)
• New feature (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality not to work as expected)

Checklist

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• I have added tests that prove my fix is useful or that my feature works
• I have added necessary documentation (if appropriate)
• I know that my PR will be merged only if it has tests and they pass

Further comments

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Fixes:

1. Unintentional autofocusing functionality on Android with the PaymentCardTextField component
2. Replaces currentlyFocusedField call (currentlyFocusedField is deprecated and will be removed in a future release. #680)