feat(themes): remove theme config function props object encapsulation

[mlmoravek]

As of #743, the second parameter of the ClassFunction theme config contains only the props of a component.
This prop object is currently wrapped in another object due to legacy implementation.

In this PR, I remove the object encapsulation for the second parameter of the ClassFunction for theme config.
This will break current theme configuration implementations.

Proposed Changes

• remove props object encapsulation

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 54.62%. Comparing base (484cfe8) to head (94846e3).
Report is 78 commits behind head on develop.

❗ Current head 94846e3 differs from pull request most recent head 7f21219

Please upload reports for the commit 7f21219 to get more accurate results.

Files	Patch %	Lines
...ckages/oruga-next/src/composables/defineClasses.ts	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #760      +/-   ##
===========================================
- Coverage    56.71%   54.62%   -2.10%     
===========================================
  Files           30       32       +2     
  Lines         1511     1461      -50     
  Branches       544      519      -25     
===========================================
- Hits           857      798      -59     
- Misses         654      663       +9     

Flag	Coverage Δ
oruga-next	54.62% <0.00%> (-2.10%)	⬇️

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