fix typo in shell script

[treerink]

@klauswyser actually it is not a typo: see here for instance. Anyway, did you experience difficulties with it such that adjustment is needed?

[klauswyser]

Thanks @treerink , you are right. Sorry, I didn't know that >& and &> are equivalent. Actually your form &> is better, here is from the bash mapage:

       There  are two formats for redirecting standard output and standard er‐
       ror:

              &>word
       and
              >&word

       Of the two forms, the first is preferred.

(The reason is that if word is a number the meaning of >& changes while &> always means redirect stderr to stdout.)

I retract this MR.