[midPoint-git] [Evolveum/prism] 7670e7: Fix determination of global item definition

[mederly]

  Branch: refs/heads/feature/attributes-as-polystrings
  Home:   https://github.com/Evolveum/prism
  Commit: 7670e747a4fe6347d4a6f0563ab871b711606e82
      https://github.com/Evolveum/prism/commit/7670e747a4fe6347d4a6f0563ab871b711606e82
  Author: Pavol Mederly <mederly at evolveum.com>
  Date:   2023-12-28 (Thu, 28 Dec 2023)

  Changed paths:
    M infra/prism-impl/src/main/java/com/evolveum/midpoint/prism/impl/schema/SchemaRegistryImpl.java

  Log Message:
  -----------
  Fix determination of global item definition

The change needed for shadow caching (polystring attributes) was too
harsh, breaking TestStrings. This commit refines it a little.

Related to MID-2119 (shadow caching).