fix(rtl): fix rtl back button default (#17109)

Closes #15357

Author: adamdbradley

core/src/components/back-button/back-button.tsx

@@ -72,9 +72,13 @@ export class BackButton implements ComponentInterface {
 
   render() {
     const defaultBackButtonText = this.mode === 'ios' ? 'Back' : null;
-    const backButtonIcon = this.icon != null ? this.icon : this.config.get('backButtonIcon', 'arrow-back');
     const backButtonText = this.text != null ? this.text : this.config.get('backButtonText', defaultBackButtonText);
 
+    let backButtonIcon = this.icon != null ? this.icon : this.config.get('backButtonIcon', 'arrow-back');
+    if (backButtonIcon === 'arrow-back' && document.dir === 'rtl') {
+      backButtonIcon = 'arrow-forward';
+    }
+
     return (
       <button
         type="button"