(core) Implementing search on raw data view

Summary:
Search now works on Raw Data Page.
- Search bar option 'Search on all pages' will change to 'Search on all tables' when on the Raw data page, and will allow searching through all tables.
- Little CSS adjustment for an overlay on Raw page (removes z-index as it is not needed, and conflicts with searchbar).
- Search bar option ('search on all') gets white background, little padding, and is moved 2 pixels up, this is needed for Raw page.

Test Plan: new and updated tests

Reviewers: georgegevoian

Reviewed By: georgegevoian

Differential Revision: https://phab.getgrist.com/D3376

app/client/components/DataTables.ts

@@ -49,7 +49,10 @@ export class DataTables extends Disposable {
             cssItem(
               testId('table'),
               cssItemContent(
-                cssIcon('TypeTable'),
+                cssIcon('TypeTable',
+                  // Element to click in tests.
+                  dom.domComputed(use => `table-id-${use(tableRec.tableId)}`)
+                ),
                 cssLabels(
                   cssTitleLine(
                     cssLine(