Fix: Don't show the find-in-page bar if it's hidden (#5381)

Task/Issue URL:
https://app.asana.com/0/1207418217763355/1205772199506591/f

### Description

This fix prevents showing the find-in-page bar when changing the omnibar
position.

### Steps to test this PR

- [x] Go to any URL
- [x] Perform a find in page search for any text
- [x] Dismiss the find in page bar
- [x] Go into settings & switch omnibar to the opposite position
- [x] Notice the find in page toolbar is not visible
- [x] Switch the omnibar position again

app/src/main/java/com/duckduckgo/app/browser/omnibar/Omnibar.kt

@@ -618,6 +618,7 @@ class Omnibar(
             binding.focusDummy.requestFocus()
             findInPage.findInPageContainer.gone()
             findInPage.findInPageInput.hideKeyboard()
+            findInPage.findInPageInput.text.clear()
         }
     }