chore(spanner): fix comment

Author: harshachinta

google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionManagerImpl.java

@@ -81,8 +81,8 @@ public void commit() {
       txnState = TransactionState.COMMIT_FAILED;
       throw e2;
     } finally {
-      // At this point, if the TransactionState is not ABORTED, then the transaction has reached a
-      // terminal state.
+      // At this point, if the TransactionState is not ABORTED, then the transaction has reached an
+      // end state.
       // We can safely call close() to release resources.
       if (getState() != TransactionState.ABORTED) {
         close();
@@ -99,7 +99,7 @@ public void rollback() {
       txn.rollback();
     } finally {
       txnState = TransactionState.ROLLED_BACK;
-      // At this point, the TransactionState is ROLLED_BACK which is a terminal state.
+      // At this point, the TransactionState is ROLLED_BACK which is an end state.
       // We can safely call close() to release resources.
       close();
     }