Use Qt:: directly

autotests/CMakeLists.txt

@@ -18,7 +18,7 @@ macro(ADD_KMIME_TEST)
     add_test(NAME kmime-${_testName} COMMAND ${_testName})
     target_link_libraries(${_testName}
       KF5Mime
-      Qt${QT_MAJOR_VERSION}::Test
+      Qt::Test
       KF5::Codecs
     )
     if (TARGET Qt6::Core5Compat)

src/CMakeLists.txt

@@ -61,7 +61,7 @@ endif()
 
 target_link_libraries(KF5Mime
 PUBLIC
-    Qt${QT_MAJOR_VERSION}::Core
+    Qt::Core
 PRIVATE
     KF5::I18n
     KF5::Codecs