Fix(Documentation): Fixed ConfigurationStrSubstitutor dccumenation. (apache#3381)

Author: jaykataria1111

log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ConfigurationStrSubstitutor.java

@@ -20,7 +20,7 @@
 import java.util.Properties;
 
 /**
- * {@link RuntimeStrSubstitutor} is a {@link StrSubstitutor} which only supports recursive evaluation of lookups.
+ * {@link ConfigurationStrSubstitutor} is a {@link StrSubstitutor} which only supports recursive evaluation of lookups.
  * This can be dangerous when combined with user-provided inputs, and should only be used on data directly from
  * a configuration.
  */