Update to Transient v0.7.2-1-gf273c0c8

Update to Transient v0.7.2-1-gf273c0c8

This fixes two bugs, one of them restoring compatibility with the
version that ships with Emacs 29, making emoji-insert usable again.
The other changes are of cosmetic nature.  The only exception is a new
command, whose creation lead to the discovery of one of the bugs, and
remains unused until a package author actually binds it in a prefix.
I.e., unless someone actually uses this, the risk of a regression is
close to zero, and even if it is used, it can only affect the prefix
that binds it.