fix(accordion-group): remove global styles

Author: brandyscarney

core/src/css/ionic/core.ionic.scss

@@ -309,9 +309,6 @@ ion-accordion-group.accordion-group-expand-inset > ion-accordion:last-of-type {
   border-bottom-left-radius: globals.$ionic-border-radius-200;
   border-bottom-right-radius: globals.$ionic-border-radius-200;
 }
-ion-accordion-group > ion-accordion:last-of-type ion-item[slot="header"] {
-  --border-width: 0;
-}
 
 ion-accordion.accordion-animated > [slot="header"] .ion-accordion-toggle-icon {
   transition: 300ms transform cubic-bezier(0.25, 0.8, 0.5, 1);
@@ -334,16 +331,6 @@ ion-accordion.accordion-expanded > [slot="header"] .ion-accordion-toggle-icon {
   transform: rotate(180deg);
 }
 
-ion-accordion-group.accordion-group-expand-inset.md > ion-accordion.accordion-previous ion-item[slot="header"] {
-  --border-width: 0;
-  --inner-border-width: 0;
-}
-
-ion-accordion-group.accordion-group-expand-inset.md > ion-accordion.accordion-expanding:first-of-type,
-ion-accordion-group.accordion-group-expand-inset.md > ion-accordion.accordion-expanded:first-of-type {
-  margin-top: 0;
-}
-
 // Safari/iOS 15 changes the appearance of input[type="date"].
 // For backwards compatibility from Ionic 5/Safari 14 designs,
 // we override the appearance only when using within an ion-input.