Added event trigger extension method for @ontoggle

[egil]

Pull request description

Closes #214

PR meta checklist

• Pull request is targeting at DEV branch.
• Pull request is linked to all related issues, if any.
• I have read the CONTRIBUTING.md document.

Content checklist

• My code follows the code style of this project and AspNetCore coding guidelines.
• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
• I have updated the appropriate sub section in the CHANGELOG.md.
• I have added, updated or removed tests to according to my changes.
  • All tests passed.

[codecov]

Codecov Report

Merging #256 (66640ab) into dev (d66c69d) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev     #256      +/-   ##
==========================================
+ Coverage   80.38%   80.39%   +0.01%     
==========================================
  Files         109      110       +1     
  Lines        3456     3458       +2     
  Branches      443      443              
==========================================
+ Hits         2778     2780       +2     
  Misses        543      543              
  Partials      135      135              

Impacted Files	Coverage Δ
...ensions/DetailsElementEventDispatcherExtensions.cs	100.00% <100.00%> (ø)

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