Bound-with-parts gets an empty collection

Steps to Reproduce:

1. Create or find an instance record that has at least one holdings record with no items attached, and no bound-with titles.
2. Send a request to /inventory/instances for the instance record with that id
3. Check the mod-inventory-storage logs for an error message indicating a failed boundwithparts lookup. You can see it in the mod-inventory logs by dumping the body of the request to the bound-with-parts endpoint.

Log messages:

2021-10-14 17:21:17.753,"10.23.36.230, 10.23.38.175, 10.23.36.78, 10.23.36.29 - 10.23.38.175 - - [14/Oct/2021:17:21:17 +0000] ""GET /mod-inventory-storage/inventory-storage/bound-with-parts?query=itemId%3D%3D%28%29&limit=0&offset=0 HTTP/1.1"" 400 137 rt=0.003 uct=""0.000"" uht=""0.004"" urt=""0.004"" ""Vert.x-WebClient/4.0.2"" ""fs00001034"" ""b6bfbac0-5cad-4ca1-aff7-0596a73128de"" ""053949/inventory;413798/inventory-storage"""
2021-10-14 17:21:17.371,17:21:17 [] [] [] [] INFO Items GET all items: all futures completed
2021-10-14 17:21:17.371,"17:21:17 [] [] [] [] ERROR Items Failed to retrieve bound-with parts, status code: 400"
2021-10-14 17:21:17.369, at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) [ms.jar:?]
2021-10-14 17:21:17.369,"Caused by: org.folio.cql2pgjson.exception.QueryValidationException: org.z3950.zing.cql.CQLParseException: expected index or term, got ')'"
2021-10-14 17:21:17.369,"17:21:17 [] [] [] [] ERROR PgUtil org.folio.cql2pgjson.exception.QueryValidationException: org.z3950.zing.cql.CQLParseException: expected index or term, got ')'"
2021-10-14 17:21:17.369,"org.folio.rest.persist.cql.CQLQueryValidationException: org.folio.cql2pgjson.exception.QueryValidationException: org.z3950.zing.cql.CQLParseException: expected index or term, got ')'