[cssom-view-1] Fix remaining IDL instances of "bool"

This is a follow-up to #7162 to fix occurrences of `bool` that were missed in
the previous PR.

Author: tidoust

cssom-view-1/Overview.bs

@@ -1042,10 +1042,10 @@ dictionary ScrollIntoViewOptions : ScrollOptions {
 };
 
 dictionary IsVisibleOptions {
-    bool checkAriaHidden = false;
-    bool checkInert = false;
-    bool checkOpacity = false;
-    bool checkVisibilityCSS = false;
+    boolean checkAriaHidden = false;
+    boolean checkInert = false;
+    boolean checkOpacity = false;
+    boolean checkVisibilityCSS = false;
 };
 
 partial interface Element {