Reinstate Spring for GraphQL auto-configuration

This commit adds the Spring for GraphQL auto-configuration back
into Spring Boot 3.0, now that a 1.1.0 release is scheduled with the
required baseline. This release also needs GraphQL Java 19.0 as a
baseline.

Closes gh-31809

spring-boot-project/spring-boot-devtools/src/main/resources/org/springframework/boot/devtools/env/devtools-property-defaults.properties

@@ -4,6 +4,7 @@ server.error.include-stacktrace=always
 server.servlet.jsp.init-parameters.development=true
 server.servlet.session.persistent=true
 spring.freemarker.cache=false
+spring.graphql.graphiql.enabled=true
 spring.groovy.template.cache=false
 spring.h2.console.enabled=true
 spring.mustache.servlet.cache=false