fix(ripple): ensure _ripple data is not undefined

[floryst]

Description

Instead of assuming element._ripple won't be undefined/null (which it could be), verify that this is the case.

Motivation and Context

Deleting a v-btn on click results in a console error "Cannot set property 'touched' of undefined at ripple.ts:148". This occurs when the ripple directive's unbind() function is called before rippleHide()'s setTimeout finishes.

Steps to reproduce (codepen):

1. Open browser devtools console
2. Click on the "delete me" button in the test page
3. Observe the error message in the console

How Has This Been Tested?

visually (added the undefined guard manually to a vuetify build)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Improvement/refactoring (non-breaking change that doesn't add any feature but make things better)

Checklist:

• The PR title is no longer than 64 characters.
• The PR is submitted to the correct branch (master for bug fixes and documentation updates, dev for new features and breaking changes).
• My code follows the code style of this project.
• I've added relevant changes to the documentation (applies to new features and breaking changes in core library)

[codecov]

Codecov Report

Merging #6476 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #6476      +/-   ##
=========================================
+ Coverage    85.6%   85.6%   +<.01%     
=========================================
  Files         298     298              
  Lines        7160    7162       +2     
  Branches     1781    1782       +1     
=========================================
+ Hits         6129    6131       +2     
  Misses        941     941              
  Partials       90      90

Impacted Files	Coverage Δ
packages/vuetify/src/directives/ripple.ts	75.59% <100%> (+0.39%)	⬆️

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[tobiasdalhof]

This PR will probably fix #6477

[MajesticPotatoe]

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[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs. Please direct any non-bug questions to our Discord