Fix (v-c-tooltip): not hiding tooltips on component unmount

[DavidWaysczak]

We found a bug on the coreui tooltip feature. The tooltips where not hiding if binding component was unmount. E.g. on click of a button with a router link and a tooltip.

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• Bugfix
• Feature
• Code style update
• Refactor
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Does this PR introduce a breaking change? (check one)

• Yes
• No

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• All tests are passing
• New/updated tests are included

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• A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

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[github-actions]

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