[m-rev.] for post-commit review: stop accepting : as module name separator

[Peter Wang]

On Fri, 11 Nov 2022 03:04:03 +1100 "Zoltan Somogyi" <zoltan.somogyi at runbox.com> wrote:
> The one question is: does this need an entry in NEWS?
> We switched to using . instead of : as module name separator
> in 2003.
> 

It wouldn't hurt to add a short item:

    We no longer accept : as the module name separator in backquoted
    operators.

Not that I expect any code to be affected.

Peter