designer table improvements (#19785)

* designer table improvements

* remove async

src/sql/base/browser/ui/table/plugins/buttonColumn.plugin.ts

@@ -45,7 +45,8 @@ export class ButtonColumn<T extends Slick.SlickData> extends BaseClickableColumn
 			name: this.options.name,
 			toolTip: this.options.title,
 			resizable: this.options.resizable,
-			selectable: false
+			selectable: false,
+			cssClass: 'slick-plugin-button-cell'
 		};
 	}
 }

src/sql/base/browser/ui/table/plugins/media/buttonColumn.plugin.css

@@ -7,9 +7,7 @@
 	cursor: pointer;
 	height: 100%;
 	text-align: center;
-	padding-right: 0px;
-	padding-top: 0px;
-	padding-bottom: 0px;
+	padding: 0px;
 }
 
 .slick-plugin-button:disabled {
@@ -32,3 +30,7 @@
 	border-width: 0px;
 	background-color: transparent;
 }
+
+.slick-plugin-button-cell {
+	text-align: center;
+}