fix(keyboard): submit form with <button/> on [Enter]

[ph-fritsche]

What:

Given an HTMLFormElement that contains both an HTMLInputElement and a HTMLButtonElement, submit the form when [Enter] is pressed on the input element.

Why:
Closes #802

Checklist:

• Tests
• Ready to be merged

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[codecov]

Codecov Report

Merging #808 (8f53ed6) into beta (32c6326) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##              beta      #808   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           77        77           
  Lines         1570      1567    -3     
  Branches       560       557    -3     
=========================================
- Hits          1570      1567    -3     

Impacted Files	Coverage Δ
src/utils/misc/hasFormSubmit.ts	100.00% <100.00%> (ø)

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[github-actions]

🎉 This PR is included in version 14.0.0-beta.3 🎉

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