Fix UI mis-align for PR commit history (#20845)

Author: wxiaoguang

web_src/less/_repository.less

@@ -906,6 +906,7 @@
 
           .singular-commit {
             line-height: 34px; /* this must be same as .badge height, to avoid overflow */
+            clear: both; // reset the "float right shabox", in the future, use flexbox instead
 
             > .avatar.image,
             > .avatar.image img {