Draft: community/kcalendarcore: bump to test x86 build in CI

as this is still failing tests on build-edge-x86, I suspect it was never tested on a CI builder, !72504 (merged)

https://build.alpinelinux.org/buildlogs/build-edge-x86/community/kcalendarcore/kcalendarcore-6.6.0-r0.log