Update URL to Gradle Shadow transformer

Author: ppkarwasz

src/site/antora/modules/ROOT/pages/faq.adoc

@@ -325,5 +325,5 @@ https://logging.staged.apache.org/log4j/transform/log4j-transform-maven-shade-pl
 
 https://gradleup.com/shadow/[Gradle Shadow Plugin]:::
 You need to use the
-https://github.com/GradleUp/shadow/blob/main/src/main/groovy/com/github/jengelman/gradle/plugins/shadow/transformers/Log4j2PluginsCacheFileTransformer.groovy[`Log4j2PluginsCacheFileTransformer`].
+https://gradleup.com/shadow/configuration/merging/#merging-log4j2-plugin-cache-files-log4j2plugins-dat[`Log4j2PluginsCacheFileTransformer`].
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