add org.apache.sling.installer.core 3.14.2

https://github.com/jvm-repo-rebuild/reproducible-central/blob/master/content/org/apache/sling/org.apache.sling.installer.core/README.md

content/org/apache/sling/org.apache.sling.installer.core/org.apache.sling.installer.core-3.14.2.buildspec

@@ -0,0 +1,18 @@
+groupId=org.apache.sling
+artifactId=org.apache.sling.installer.core
+display=${groupId}:.installer.core
+version=3.14.2
+
+gitRepo=https://github.com/apache/sling-$(echo ${artifactId} | tr '.' '-').git
+gitTag=${artifactId}-${version}
+
+tool=mvn-3.9.9
+jdk=17
+newline=lf
+umask=022
+
+command="mvn -Papache-release clean package -DskipTests -Dmaven.javadoc.skip -Dgpg.skip"
+buildinfo=target/${artifactId}-${version}.buildinfo
+
+#diffoscope=${artifactId}-${version}.diffoscope
+issue=