(core) Hides the link icon in print view

Summary:
Users complained about white spaces left by the link icon when printing.
Diff fixes the issue by hiding link icon completely.

Test Plan: Adds tests in `nbrowser/Printing.ts`

Reviewers: jarek

Reviewed By: jarek

Differential Revision: https://phab.getgrist.com/D3767

app/client/ui2018/links.ts

@@ -1,5 +1,5 @@
 import { sameDocumentUrlState, urlState } from 'app/client/models/gristUrlState';
-import { theme } from 'app/client/ui2018/cssVars';
+import { hideInPrintView, theme } from 'app/client/ui2018/cssVars';
 import { CellValue } from 'app/plugin/GristData';
 import { dom, IDomArgs, Observable, styled } from 'grainjs';
 
@@ -30,6 +30,7 @@ export function gristLink(href: string|Observable<string>, ...args: IDomArgs<HTM
     // from running on the same process as Grist:
     // https://developers.google.com/web/tools/lighthouse/audits/noopener
     dom.attr("rel", "noopener noreferrer"),
+    hideInPrintView(),
     args
   );
 }