chore: cleanup two deprecated (3+ years) GQL fields

[omBratteng]

Post placeholder has been deprecated for at least 3 years, same with ratio.
https://github.com/dailydotdev/daily-api/blame/ab1a21106e1cf6ab665f5e5a0348355f1eac17bf/src/schema/posts.ts#L478-L481

Removed in dailydotdev/apps#4125 (was only queried by SSR, not client side).

[pulumi]

🍹 The Update (preview) for dailydotdev/api/prod was successful.

Resource Changes

    Name                                            Type                           Operation
~   vpc-native-validate-active-users-cron           kubernetes:batch/v1:CronJob    update
~   vpc-native-sync-subscription-with-cio-cron      kubernetes:batch/v1:CronJob    update
~   vpc-native-update-source-tag-view-cron          kubernetes:batch/v1:CronJob    update
~   vpc-native-bg-deployment                        kubernetes:apps/v1:Deployment  update
~   vpc-native-generic-referral-reminder-cron       kubernetes:batch/v1:CronJob    update
~   vpc-native-calculate-top-readers-cron           kubernetes:batch/v1:CronJob    update
~   vpc-native-personalized-digest-deployment       kubernetes:apps/v1:Deployment  update
~   vpc-native-update-current-streak-cron           kubernetes:batch/v1:CronJob    update
~   vpc-native-update-source-public-threshold-cron  kubernetes:batch/v1:CronJob    update
~   vpc-native-clean-zombie-user-companies-cron     kubernetes:batch/v1:CronJob    update
-   vpc-native-api-migration-db35fba7               kubernetes:batch/v1:Job        delete
~   vpc-native-private-deployment                   kubernetes:apps/v1:Deployment  update
~   vpc-native-deployment                           kubernetes:apps/v1:Deployment  update
~   vpc-native-hourly-notification-cron             kubernetes:batch/v1:CronJob    update
~   vpc-native-update-tag-recommendations-cron      kubernetes:batch/v1:CronJob    update
~   vpc-native-temporal-deployment                  kubernetes:apps/v1:Deployment  update
~   vpc-native-clean-gifted-plus-cron               kubernetes:batch/v1:CronJob    update
~   vpc-native-update-highlighted-views-cron        kubernetes:batch/v1:CronJob    update
+   vpc-native-api-migration-d6244497               kubernetes:batch/v1:Job        create
~   vpc-native-update-views-cron                    kubernetes:batch/v1:CronJob    update
~   vpc-native-ws-deployment                        kubernetes:apps/v1:Deployment  update
~   vpc-native-clean-zombie-images-cron             kubernetes:batch/v1:CronJob    update
~   vpc-native-update-tags-str-cron                 kubernetes:batch/v1:CronJob    update
+-  vpc-native-k8s-secret                           kubernetes:core/v1:Secret      create-replacement
~   vpc-native-clean-zombie-users-cron              kubernetes:batch/v1:CronJob    update
~   vpc-native-update-trending-cron                 kubernetes:batch/v1:CronJob    update
~   vpc-native-generate-search-invites-cron         kubernetes:batch/v1:CronJob    update
~   vpc-native-daily-digest-cron                    kubernetes:batch/v1:CronJob    update
~   vpc-native-check-analytics-report-cron          kubernetes:batch/v1:CronJob    update
~   vpc-native-personalized-digest-cron             kubernetes:batch/v1:CronJob    update