Remove custom SecurityManager (elastic#127778)

Since SecurityManager is no longer used, the custom subclass of
SecurityManager, SecureSM, is no longer needed.

Author: rjernst

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/InternalDistributionModuleCheckTaskProvider.java

@@ -60,7 +60,6 @@ public class InternalDistributionModuleCheckTaskProvider {
         "org.elasticsearch.nativeaccess",
         "org.elasticsearch.plugin",
         "org.elasticsearch.plugin.analysis",
-        "org.elasticsearch.securesm",
         "org.elasticsearch.server",
         "org.elasticsearch.simdvec",
         "org.elasticsearch.tdigest",