Auto merge of #23171 - hundredeir:find_elem_elems, r=jdm

add webdriver command "Find elements from Element"

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because ___

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components/script/script_thread.rs

@@ -1884,6 +1884,15 @@ impl ScriptThread {
                     reply,
                 )
             },
+            WebDriverScriptCommand::FindElementElementsCSS(selector, element_id, reply) => {
+                webdriver_handlers::handle_find_element_elements_css(
+                    &*documents,
+                    pipeline_id,
+                    element_id,
+                    selector,
+                    reply,
+                )
+            },
             WebDriverScriptCommand::FocusElement(element_id, reply) => {
                 webdriver_handlers::handle_focus_element(
                     &*documents,