fix base commit in README.md

Author: mqy

examples/mulmat-tune/README.md

@@ -63,12 +63,12 @@ on MacBook Pro 2018 with 32 GB 2400 MHz DDR4 memory, 2.6 GHz 6-Core Intel Core
 i7-8850H @2.60GHz, Intel UHD Graphics 630 1536 MB.
 
 When you read the following sections, please note that current incoming codes are
-based on this commit:
+based on this commit and fragile to forced pushing:
 
 ```
-commit 66874d4fbcc7866377246efbcee938e8cc9c7d76 (origin/master, origin/HEAD)
-Author: Kerfuffle <[email protected]>
-Date:   Thu May 25 20:18:01 2023 -0600
+commit 3b126f654fceb4f5f195a1c2e825bb18e101188c
+Author: Johannes Gäßler <[email protected]>
+Date:   Sun May 28 21:01:02 2023 +0200
 ```
 
 ## Solution and Result