Update margins to match in template editor view and main page view

varia/sass/full-site-editing/_editor.scss

@@ -5,6 +5,13 @@
 			margin-right: 0;
 		}
 	}
+
+	// Match margins for template parts rendered in the page and template part editor view.
+	.block-editor-block-list__block-edit {
+		[data-block] {
+			margin: 12px 0 0 0;
+		}
+	}
 }
 
 .template-block {