Improve Tooltip example: Add onBlur event

[wasutz]

Currently, we cannot see the Tooltip if the user just clicks the input and did not type anything.
I think it can be improved by adding onBlur event.

[vercel]

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[codecov]

Codecov Report

Merging #196 into master will not change coverage.
The diff coverage is n/a.

@@ Coverage Diff @@## master #196 +/- ##
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Coverage 88% 88% =====================================
Files 3 3 Lines 25 25 Branches 10 10 =====================================
Hits 22 22 Misses 3 3

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