Bug 1242529: [Usable - Azure Cosmos DB - Input Parameters]: Aria-label is not descriptive enough for the 'Close(x)' button of 'Input Parameters' blade. (#1760)

* screen reader name for the button has been changed to read out the name of the dialog box

* tests have been updated

src/Explorer/Panes/PanelContainerComponent.tsx

@@ -58,7 +58,7 @@ export class PanelContainerComponent extends React.Component<PanelContainerProps
         onDismiss={this.onDissmiss}
         isLightDismiss
         type={PanelType.custom}
-        closeButtonAriaLabel="Close"
+        closeButtonAriaLabel={`Close ${this.props.headerText}`}
         customWidth={this.props.panelWidth ? this.props.panelWidth : "440px"}
         headerClassName="panelHeader"
         onRenderNavigationContent={this.props.onRenderNavigationContent}