MINOR: fix typo in StandardAuthorizer, StandardAuthorizerDelta, KafkaConfigSchema and MigrationClient files

metadata/src/main/java/org/apache/kafka/metadata/KafkaConfigSchema.java

@@ -210,7 +210,7 @@ private ConfigEntry toConfigEntry(ConfigDef.ConfigKey configKey,
                                       Object value,
                                       ConfigSource source,
                                       Function<String, String> converter) {
-        // Convert the value into a nulllable string suitable for storing in ConfigEntry.
+        // Convert the value into a nullable string suitable for storing in ConfigEntry.
         String stringValue = null;
         if (value != null) {
             if (value instanceof String) {

metadata/src/main/java/org/apache/kafka/metadata/authorizer/StandardAuthorizer.java

@@ -55,7 +55,7 @@ public class StandardAuthorizer implements ClusterMetadataAuthorizer {
     public final static String ALLOW_EVERYONE_IF_NO_ACL_IS_FOUND_CONFIG = "allow.everyone.if.no.acl.found";
 
     /**
-     * A future which is completed once we have loaded up to the initial high water mark.
+     * A future which is completed once we have loaded up to the initial high watermark.
      */
     private final CompletableFuture<Void> initialLoadFuture = new CompletableFuture<>();
 

metadata/src/main/java/org/apache/kafka/metadata/authorizer/StandardAuthorizerData.java

@@ -525,7 +525,7 @@ static AuthorizationResult findResult(Action action,
         }
         // Check if the operation field matches. Here we hit a slight complication.
         // ACLs for various operations (READ, WRITE, DELETE, ALTER), "imply" the presence
-        // of DESCRIBE, even if it isn't explictly stated. A similar rule applies to
+        // of DESCRIBE, even if it isn't explicitly stated. A similar rule applies to
         // DESCRIBE_CONFIGS.
         //
         // But this rule only applies to ALLOW ACLs. So for example, a DENY ACL for READ

metadata/src/main/java/org/apache/kafka/metadata/migration/MigrationClient.java

@@ -40,7 +40,7 @@ public interface MigrationClient {
      * Read or initialize the ZK migration leader state in ZK. If the ZNode is absent, the given {@code initialState}
      * will be written and subsequently returned with the zkVersion of the node. If the ZNode is present, it will be
      * read and returned.
-     * @param initialState  An initial, emtpy, state to write to ZooKeeper for the migration state.
+     * @param initialState  An initial, empty, state to write to ZooKeeper for the migration state.
      * @return  The existing migration state, or the initial state given.
      */
     ZkMigrationLeadershipState getOrCreateMigrationRecoveryState(ZkMigrationLeadershipState initialState);