When quiz name contains quotes, xlsx/ods files, downloaded from grade report are invalid.

Steps to reproduce:

1. Create quiz with name <test with "quotes">.
2. Make some attempts for it as student.
3. Go to results -> grades and download report as excel or opendocument.
4. Downloaded file is invalid.

If you unzip ods file in content.xml  line 9 you can see something like this:

</style:style></office:automatic-styles><office:body><office:spreadsheet><table:table table:style-name="ta1" table:name="TSTCRS test with "quotes""><table:table-column table:default-cell-style-name="ce1" ...

table:name (sheet title?) tag isn't escaped.