Exclude target directories from checkstyleNohttp source inputs

The kerberos-client/target and kerberos-test/target directories contain
.keytab files generated during test execution. These directories only
exist after the first build, causing a cache miss for checkstyleNohttp
in subsequent builds since the source input set changes.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ribafish

build.gradle

@@ -80,7 +80,7 @@ develocity {
 }
 
 nohttp {
-	source.exclude "buildSrc/build/**", "**/build/**", "javascript/.gradle/**", "javascript/package-lock.json", "javascript/node_modules/**", "javascript/build/**", "javascript/dist/**"
+	source.exclude "buildSrc/build/**", "**/build/**", "**/target/**", "javascript/.gradle/**", "javascript/package-lock.json", "javascript/node_modules/**", "javascript/build/**", "javascript/dist/**"
 	source.builtBy(project(':spring-security-config').tasks.withType(RncToXsd))
 }