tdf#42949 Fix IWYU warnings in include/jvmaccess/*

Found with bin/find-unneeded-includes
Only removal proposals are dealt with here.

Change-Id: I404b1ff3c312e5168a6dfec0133092dda640e155
Reviewed-on: https://gerrit.libreoffice.org/61508
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>

include/jvmaccess/classpath.hxx

@@ -24,15 +24,15 @@
 
 #include <jni.h>
 
-#include <com/sun/star/uno/Reference.hxx>
 #include <jvmaccess/jvmaccessdllapi.h>
 #include <rtl/ustring.hxx>
-#include <sal/types.h>
 
 namespace com { namespace sun { namespace star { namespace uno {
     class XComponentContext;
 } } } }
 
+namespace com { namespace sun { namespace star { namespace uno { template <typename > class Reference; } } } }
+
 namespace jvmaccess {
 
 /**