Establish baseline webdriver conformance results (#35024)

https://github.com/web-platform-tests/wpt/pull/50041 allows us to start
running the webdriver conformance tests in Servo, which will make it
easier for us to track regressions/improvements in our webdriver server
implementation.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes are part of #15274
- [x] There are tests for these changes

---------

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

tests/wpt/meta/html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/iframe-nosrc.html.ini

@@ -2,8 +2,5 @@
   [window.open]
     expected: FAIL
 
-  [link click]
-    expected: FAIL
-
   [form submission]
     expected: FAIL

tests/wpt/meta/html/canvas/element/manual/imagebitmap/createImageBitmap-transfer.html.ini

@@ -1,5 +1,5 @@
 [createImageBitmap-transfer.html]
-  expected: TIMEOUT
+  expected: ERROR
   [Transfer ImageBitmap created from a vector HTMLImageElement]
     expected: FAIL
 

tests/wpt/meta/html/infrastructure/urls/base-url/document-base-url-window-initiator-is-not-opener.https.window.js.ini

@@ -1,3 +1,4 @@
 [document-base-url-window-initiator-is-not-opener.https.window.html]
+  expected: TIMEOUT
   [window.open() gets base url from initiator not opener.]
     expected: [FAIL, PASS, TIMEOUT]

tests/wpt/meta/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-1.html.ini

@@ -1,4 +1,3 @@
 [iframe_sandbox_popups_nonescaping-1.html]
-  expected: CRASH
   [Check that popups from a sandboxed iframe do not escape the sandbox]
-    expected: NOTRUN
+    expected: FAIL

tests/wpt/meta/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini

@@ -1,4 +1,3 @@
 [iframe_sandbox_popups_nonescaping-3.html]
-  expected: TIMEOUT
   [Check that popups from a sandboxed iframe do not escape the sandbox]
     expected: NOTRUN