previously, `builtins.break` didn't force its argument, resulting in
a value wrapped with `break` being opaque to most builtins if not
also wrapped with `seq`. see [lix-project/lix#1165] for more details
on what this can break.
this tiny fix just adds a call to `forceValue` inside `prim_break`,
but unfortunately this "breaks" a few existing tests because it
changes the call stack; those tests' golden outputs have been adjusted
without modifying their intended purpose.
Fixes#1165
[lix-project/lix#1165]: https://git.lix.systems/lix-project/lix/issues/1165
Change-Id: I5fe4ee3ff28b38aaf924125b8978130812e58fef