Replace $timeout with $interval

[joetinoco]

When testing with Protractor, the $timeout used to clear toasts blocks Angular until the toast goes away, and that makes it impossible to assert the toast contents, for example.

The solution, as discussed in this Protractor issue, is simply to use $interval instead of $timeout - that's what is included in this pull request.

[CLAassistant]

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1 out of 2 committers have signed the CLA.

✅ Ehesp
❌ Joe Tinoco

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