Fix compiler error in example app

[BasThomas]

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PR Summary

Fixes a compiler error in the example project

Test strategy

Run the Swift example and verify that it builds on Xcode 9

[dzenbot]

My bad. shouldProcessText(forAutoCompletion text: String was actually deprecated in favour of shouldProcessTextForAutoCompletion().
Mind updating to that method instead?

[BasThomas]

Updated. But how could it be causing a compiler error if it was deprecated? That doesn't sound right?

[dzenbot]

Because it was not longer defined on the super class, meaning we should have not been using override anymore. My bad, I always forget to check that sample project.

[BasThomas]

CI? :)

[dzenbot]

Thanks for fixing this!