SQL statements should not have PostgreSQL schema names hardcoded

[bczerwinski-equinix]

As found in the following scripts:
https://github.com/kamilkisiela/graphql-hive/tree/main/packages/migrations/src/actions
https://github.com/kamilkisiela/graphql-hive/tree/main/packages/migrations/src/clickhouse-actions

There are PostgreSQL schemas names hardcoded (like public). This collides with PostgreSQL user (role) specific search_path setting, causing errors when executing migrations and some specific schema is set using search_path.

[bczerwinski-equinix]

@n1ru4l I have searched though the entire project and for " public." (https://github.com/search?q=repo%3Akamilkisiela%2Fgraphql-hive+%22+public.%22&type=code) found multiple types of SQL statements where at least public schema is being used.

[n1ru4l]

@bczerwinski-equinix We can safely remove all these public references!