Rename metadata directories

This renames:
 - `tests/wpt/metadata` → `tests/wpt/meta-legacy-layout`
 - `tests/wpt/metadata-layout-2020` → `tests/wpt/meta`
 - `tests/wpt/mozilla/meta` → `tests/wpt/mozilla/meta-legacy-layout`
 - `tests/wpt/mozilla/meta-layout-2020` → `tests/wpt/mozilla/meta`

tests/wpt/meta/css/css-animations/Document-getAnimations.tentative.html.ini

@@ -0,0 +1,55 @@
+[Document-getAnimations.tentative.html]
+  [CSS Animations targetting (pseudo-)elements should have correct order after sorting (::marker)]
+    expected: FAIL
+
+  [Finished but not filling CSS Animations are not returned]
+    expected: FAIL
+
+  [Order of CSS Animations and CSS Transitions]
+    expected: FAIL
+
+  [Order of CSS Animations - markup-bound vs free animations]
+    expected: FAIL
+
+  [Order of CSS Animations - across elements]
+    expected: FAIL
+
+  [getAnimations for CSS Animations]
+    expected: FAIL
+
+  [Order of CSS Animations - within an element unaffected by start time]
+    expected: FAIL
+
+  [Order of CSS Animations - free animations]
+    expected: FAIL
+
+  [Order of CSS Animations - free animation vs CSS Transitions]
+    expected: FAIL
+
+  [CSS Animations canceled and restarted via the API are returned]
+    expected: FAIL
+
+  [getAnimations for non-animated content]
+    expected: FAIL
+
+  [Order of CSS Animations - across and within elements]
+    expected: FAIL
+
+  [Order of CSS Animations - within an element]
+    expected: FAIL
+
+  [CSS Animations targetting (pseudo-)elements should have correct order after sorting]
+    expected: FAIL
+
+  [CSS Animations canceled via the API are not returned]
+    expected: FAIL
+
+  [Finished but filling CSS Animations are returned]
+    expected: FAIL
+
+  [Yet-to-start CSS Animations are returned]
+    expected: FAIL
+
+  [pseudo element with replaced target does not affect animation ordering]
+    expected: FAIL
+