Removed extra border-radius from custom toast styles

src/scss/_toasts.scss

@@ -39,13 +39,6 @@
   margin: 8px;
 }
 
-//
-// Adding a bottom border radius the toast body
-//
-.toast .toast-body {
-  --#{$prefix}toast-border-radius: 0 0 .25rem .25rem;
-}
-
 //
 // Color variants
 //