MINOR: Narrow remote copy lag validator props to Map<String, ?> and update the upgrade doc for KIP-1241

docs/getting-started/upgrade.md

@@ -34,6 +34,7 @@ type: docs
 
   * The `ClientQuotaCallback#updateClusterMetadata` method is deprecated and will be removed in Kafka 5.0. Custom implementations of `ClientQuotaCallback` no longer need to override this method, as a default no-op implementation is now provided. For further details, please refer to [KIP-1200](https://cwiki.apache.org/confluence/x/axBJFg).
   * The in-memory keystores (used for PEM certificates) now use the default type provided by `KeyStore.getDefaultType()` instead of the hardcoded PKCS12 type.   
+  * New configs have been introduced: remote.copy.lag.bytes, remote.copy.lag.ms and their corresponding broker-level configurations. They allow tiered storage redundancy reduced with delayed upload. For further details, please refer to [KIP-1241](https://cwiki.apache.org/confluence/x/A4LMFw).
 
 ## Upgrading to 4.3.0
 

storage/src/main/java/org/apache/kafka/storage/internals/log/LogConfig.java

@@ -631,7 +631,7 @@ private static void validateRemoteStorageRetentionTime(Map<String, ?> props) {
         }
     }
 
-    private static void validateRemoteCopyLagTime(Map<?, ?> props) {
+    private static void validateRemoteCopyLagTime(Map<String, ?> props) {
         Long retentionMs = (Long) props.get(TopicConfig.RETENTION_MS_CONFIG);
         Long localRetentionMs = (Long) props.get(TopicConfig.LOCAL_LOG_RETENTION_MS_CONFIG);
         Long remoteCopyLagMs = (Long) props.get(TopicConfig.REMOTE_COPY_LAG_MS_CONFIG);
@@ -644,7 +644,7 @@ private static void validateRemoteCopyLagTime(Map<?, ?> props) {
         }
     }
 
-    private static void validateRemoteCopyLagSize(Map<?, ?> props) {
+    private static void validateRemoteCopyLagSize(Map<String, ?> props) {
         Long retentionBytes = (Long) props.get(TopicConfig.RETENTION_BYTES_CONFIG);
         Long localRetentionBytes = (Long) props.get(TopicConfig.LOCAL_LOG_RETENTION_BYTES_CONFIG);
         Long remoteCopyLagBytes = (Long) props.get(TopicConfig.REMOTE_COPY_LAG_BYTES_CONFIG);