Fix migration rename command in Readme
Fix migration rename command in Readme

The wildcard in the original command led to a "*" in the resulting name (see #314). Use `rename` command instead.
tf/pageflow-dependabot-test,tf/pageflow-dependabot-test,tf/pageflow-dependabot-test,tf/pageflow-dependabot-test,tf/pageflow,grgr/pageflow,codevise/pageflow,Modularfield/pageflow,codevise/pageflow,codevise/pageflow,tilsammans/pageflow,tf/pageflow,Modularfield/pageflow,Modularfield/pageflow,grgr/pageflow,tf/pageflow,grgr/pageflow,tilsammans/pageflow,Modularfield/pageflow,tilsammans/pageflow,codevise/pageflow,tilsammans/pageflow,tf/pageflow