test: HACK: Ignore .pf-v6-screen-reader sub-elements for ph_text()

Don't consider `.pf-v6-screen-reader` sub-elements of ph_text()
elements. Current PF6 version forces some extra screen-reader only junk:
patternfly/patternfly-react#11678

We will fix this properly (via PF), but it breaks a number of tests.

Author: martinpitt

test/common/test-functions.js

@@ -110,9 +110,15 @@ window.ph_text = function(sel) {
     const el = window.ph_find(sel);
     if (el.textContent === undefined)
         throw new Error(sel + " can not have text");
+
+    // HACK: https://github.com/patternfly/patternfly-react/issues/11678
+    const el_copy = el.cloneNode(true);
+    // find and clear .pf-v6-screen-reader subelements
+    el_copy.querySelectorAll('.pf-v6-screen-reader').forEach(el => { el.textContent = '' });
+
     // 0xa0 is a non-breakable space, which is a rendering detail of Chromium
     // and awkward to handle in tests; turn it into normal spaces
-    return el.textContent.replaceAll("\xa0", " ");
+    return el_copy.textContent.replaceAll("\xa0", " ");
 };
 
 window.ph_attr = function(sel, attr) {