fix(deploy): align vector bootstrap identity policy

deploy/vector/reconcile-roles.sh

@@ -1,19 +1,12 @@
 #!/bin/sh
 set -eu
 
-read_secret() {
-  value=$(cat "/run/secrets/$1")
-  if [ -z "$value" ] || printf '%s' "$value" | grep -q '[[:space:]]'; then
-    echo "$1 must be non-empty and contain no whitespace" >&2
-    exit 2
-  fi
-  printf '%s' "$value"
-}
+. /opt/thoth/secret-policy.sh
 
-export PGPASSWORD=$(read_secret vector_bootstrap_password)
-migrator_password=$(read_secret vector_migrator_password)
-reader_password=$(read_secret vector_reader_password)
-writer_password=$(read_secret vector_writer_password)
+export PGPASSWORD=$(read_secret_file /run/secrets/vector_bootstrap_password vector_bootstrap_password)
+migrator_password=$(read_secret_file /run/secrets/vector_migrator_password vector_migrator_password)
+reader_password=$(read_secret_file /run/secrets/vector_reader_password vector_reader_password)
+writer_password=$(read_secret_file /run/secrets/vector_writer_password vector_writer_password)
 
 psql --set=ON_ERROR_STOP=1 \
   --set=migrator_user="$THT_VECTOR_MIGRATOR_USER" \