JumpToPage widget doesn't display the correct suggestions when including + or & in the search box

This is caused by XWIKI-5970, but can be worked around in this specific case.

How to reproduce:
1. Create a document called "C++ is great"
2. Trigger the JumpToPage widget
3. Input C++
4. Note that this document is not returned as a suggestion (the list contains documents from the AnnotationCode space, matching the C in the space name)