Deleting branch fix/bug-34657-erc-hooks

[J.P.]

This follows from the resolution of:

  bug#34657: 26.1; Some erc hook names lack the expected suffix

To summarize, this was a proposal to rename a couple ancient hooks that
deviated from the modern convention of using the suffix "-functions" to
denote non-nullary hooks. But it was discovered the usual practice of
aliasing and deprecating might give rise to possible unwanted
complications involving various customize mechanisms. To sidestep these
issues, the hook was recast as a hook-like analog in its custom
definition.

Because of this remedy, the one patch this branch contains no longer
applies physically or otherwise (IMO). I therefore move that the branch
be deleted. If no one says anything or beats me to it, I'll go ahead and
carry this out on or around April 2, 2022. Thanks.