[MM-62724] Refresh error page screen to match branding, remove react-bootstrap (#3300)

* [MM-62724] Refresh error page screen to match branding, remove react-bootstrap

* Fix links on error page to open externally

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Co-authored-by: Mattermost Build <build@mattermost.com>

src/types/window.ts

@@ -37,7 +37,7 @@ declare global {
             exitFullScreen: () => void;
             doubleClickOnWindow: (windowName?: string) => void;
             focusCurrentView: () => void;
-            reloadCurrentView: () => void;
+            openServerExternally: () => void;
             closeDownloadsDropdown: () => void;
             closeDownloadsDropdownMenu: () => void;
             openDownloadsDropdown: () => void;