bug#72365: srfi-64: test-on-bad-end-name-simple is not allowed to raise an exception

Hello,

I think I found a bug in (srfi srfi-64) module shipped with GNU Guile.

The specification says the following about the simple test runner:

> Creates a new simple test-runner, that prints errors and a summary on the
> standard output port.

It does not mention that it can signal errors, so I believe the following should
just print to the terminal:

    (use-modules (srfi srfi-64))
    (test-on-bad-end-name-simple (test-runner-null) "x" "y")

However is signals an error instead:

    Backtrace:
    In ice-9/boot-9.scm:
      1752:10  6 (with-exception-handler _ _ #:unwind? _ #:unwind-for-type _)
    In unknown file:
               5 (apply-smob/0 #<thunk 7f6cf05a9300>)
    In ice-9/boot-9.scm:
        724:2  4 (call-with-prompt ("prompt") #<procedure 7f6cf05b6280 at ice-9/eval.scm:330:…> …)
    In ice-9/eval.scm:
        619:8  3 (_ #(#(#<directory (guile-user) 7f6cf05acc80>)))
    In ice-9/boot-9.scm:
       2836:4  2 (save-module-excursion #<procedure 7f6cf059d300 at ice-9/boot-9.scm:4393:3 ()>)
      4388:12  1 (_)
    In srfi/srfi-64/testing.scm:
       375:14  0 (test-on-bad-end-name-simple _ _ _)

    srfi/srfi-64/testing.scm:375:14: In procedure test-on-bad-end-name-simple:
    test-end x does not match test-begin y

Have a nice day
Tomas Volf