update doc

Author: cen1

quazip/doc/index.dox

@@ -68,7 +68,6 @@ you can get away with using zlib library bundled into %Qt (see below).
 CMake-wise, you need \c ZLIB::ZLIB and one of the following:
 \li \c Qt5::Core
 \li \c Qt6::Core and \c Qt6::Core5Compat (optional)
-\li \c Qt4::QtCore
 
 To build and run tests, the appropriate Test and Network submodules are needed as well.