build(nix): Fix snapshot-restore script

drop_db will never work from docker, since the database is created
by the postgresql entrypoint, so remove this from the snapshot
restore sequence

Author: sgillespie

scripts/postgresql-setup.sh

@@ -193,7 +193,6 @@ function restore_snapshot {
 	  lstate_gz_file=$(find "${tmp_dir}/" -iname "*.lstate.gz")
 	  lstate_file=$(basename "${lstate_gz_file}" | sed 's/.gz$//')
 	  gunzip --to-stdout "${lstate_gz_file}" > "$2/${lstate_file}"
-	  drop_db
 
           # Important: specify --schema=public below to skip over `create schema public`
           # statement generated by pg_dump