Change z-index value for reconnect modal. Fixes #12867 (#17512)

This changes the z-index of the Blazor reconnect modal to be aligned
with the z-index used by Bootstrap for modals overlays. If users rely on
Bootstrap for overlays within application this would prevent obstruction
of the Blazor's reconnect information with other overlays in the
application.

Addresses #12867

src/Components/Web.JS/src/Platform/Circuits/DefaultReconnectDisplay.ts

@@ -22,7 +22,7 @@ export class DefaultReconnectDisplay implements ReconnectDisplay {
       'right: 0',
       'bottom: 0',
       'left: 0',
-      'z-index: 1000',
+      'z-index: 1050',
       'display: none',
       'overflow: hidden',
       'background-color: #fff',