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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components/script_traits/webdriver_msg.rs

@@ -27,6 +27,7 @@ pub enum WebDriverScriptCommand {
     FindElementCSS(String, IpcSender<Result<Option<String>, ()>>),
     FindElementsCSS(String, IpcSender<Result<Vec<String>, ()>>),
     FindElementElementCSS(String, String, IpcSender<Result<Option<String>, ()>>),
+    FindElementElementsCSS(String, String, IpcSender<Result<Option<String>, ()>>),
     FocusElement(String, IpcSender<Result<(), ()>>),
     GetActiveElement(IpcSender<Option<String>>),
     GetCookie(String, IpcSender<Vec<Serde<Cookie<'static>>>>),