Spring-ai Replace HTTP with HTTPS in xsi of pom.xml files

Summary: The pom.xml files in the spring-ai project contain HTTP links in the xsi:schemaLocation attribute, which causes warnings in IntelliJ. These links should be updated to HTTPS to eliminate the warnings and improve security.

Details:

Only the http://maven.apache.org/xsd/maven-4.0.0.xsd part of pom.xml was triggering the warning, so I modified that part. So I replace http://maven.apache.org/xsd/maven-4.0.0.xsd to https://maven.apache.org/xsd/maven-4.0.0.xsd of all pom.xml file

The following files already have HTTPS links so I not changes: - vector-stores/spring-ai-gemfire-store/pom.xml - vector-stores/spring-ai-qdrant-storee/pom.xml - vector-stores/spring-ai-pinecone-store/pom.xml - vector-stores/spring-ai-weaviate-store/pom.xml

Environment: - IntelliJ IDEA - Project: spring-ai - File: pom.xml