Tracing: Remove newTraceViewHeader feature toggle (#71818)

* Remove TracePageHeader, uiFind, setTrace and many spanFindMatches

* Removed TracePageSearchBar

* Update useSearch

* Update filterSpans

* Update docs

* Updated tests

* Add trace to tests

* Remove feature toggle

* Renames in useSearch

* Renames in filter-spans

* Cleanup fixes

* Rename TracePageHeader

* Rename TracePageSearchBar

* Update test

* Update style for long urls

* Style and check

docs/sources/explore/trace-integration.md

@@ -59,11 +59,6 @@ Shows condensed view or the trace timeline. Drag your mouse over the minimap to
 
 ### Span Filters
 
-{{% admonition type="note" %}}
-This feature is behind the `newTraceViewHeader` [feature toggle]({{< relref "../setup-grafana/configure-grafana/feature-toggles" >}}).
-If you use Grafana Cloud, open a [support ticket in the Cloud Portal](/profile/org#support) to access this feature.
-{{% /admonition %}}
-
 ![Screenshot of span filtering](/media/docs/tempo/screenshot-grafana-tempo-span-filters.png)
 
 Using span filters, you can filter your spans in the trace timeline viewer. The more filters you add, the more specific are the filtered spans.