fix: make Key-Value widget higher [skip ci] (#252)

Since the Polaris migration of CloudWatch dashboards, the Key-Value widget does not fit into the given default height. There is a scrollbar shown. This CR raises the height by 1, which is sufficient raise.

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Author: voho

lib/dashboard/widget/KeyValueTableWidget.ts

@@ -6,7 +6,7 @@ export class KeyValueTableWidget extends TextWidget {
   constructor(data: [string, string][]) {
     super({
       width: FullWidth,
-      height: 2,
+      height: 3,
       markdown: KeyValueTableWidget.toMarkdown(data),
     });
   }