Add configuration for changelog generator

This commits adds a dedicated configuration to be used when invoking
the github changelog generator. This custom configuration makes sure
to sort dependency upgrades based on the issue title.

Closes gh-23484

ci/scripts/generate-changelog.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 set -e
 
+CONFIG_DIR=git-repo/ci/config
 version=$( cat version/version )
 
 milestone=${version}
@@ -9,7 +10,7 @@ if [[ $RELEASE_TYPE = "RELEASE" ]]; then
 fi
 
 java -jar /github-changelog-generator.jar \
-  --changelog.repository=spring-projects/spring-boot  \
+  --spring.config.location=${CONFIG_DIR}/changelog-generator.yml \
   ${milestone} generated-changelog/changelog.md
 
 echo ${version} > generated-changelog/version