Fix hover docs for class fields (#315)

It used to show docs of the enclosing class.

Author: nya3jp

src/main/java/org/javacs/hover/HoverProvider.java

@@ -109,7 +109,7 @@ private String docs(CompileTask task, Element element) {
             var file = compiler.findAnywhere(className);
             if (file.isEmpty()) return "";
             var parse = compiler.parse(file.get());
-            var tree = FindHelper.findType(parse, className);
+            var tree = FindHelper.findField(parse, className, field.getSimpleName().toString());
             return docs(parse, tree);
         } else if (element instanceof ExecutableElement) {
             var method = (ExecutableElement) element;