fix(checkbox, radio-button): fixed error message font-size for Ionic theme (#30836)

Issue number: resolves #

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## What is the current behavior?
- Checkbox and RadioGroup font-size was medium regular (14px)

## What is the new behavior?
- Checkbox and RadioGroup are now with font-size small regular (12px)

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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Co-authored-by: ionitron <[email protected]>

Author: joselrio

core/src/components/checkbox/checkbox.ionic.scss

@@ -113,7 +113,7 @@ input {
 // ----------------------------------------------------------------
 
 .checkbox-bottom {
-  @include globals.typography(globals.$ion-body-md-regular);
+  @include globals.typography(globals.$ion-body-sm-medium);
 }
 
 .checkbox-bottom .error-text {