Fix CMake package version compatibility checking

We're compatible across minor versions, only the major version change
would mean incompatibility. This way for example find_package(Slint 1.6.0)
will work with newer versions and makes it a minimum version specifier.

api/cpp/CMakeLists.txt

@@ -440,7 +440,7 @@ if(SLINT_BUILD_RUNTIME)
     write_basic_package_version_file(
         ${CMAKE_CURRENT_BINARY_DIR}/lib/cmake/Slint/SlintConfigVersion.cmake
         VERSION ${PROJECT_VERSION}
-        COMPATIBILITY SameMinorVersion
+        COMPATIBILITY SameMajorVersion
     )
 
     install(FILES