Fix false negatives in lean_startup.t

Fix false negatives in lean_startup.t

Before this commit a 'use Devel::Dwarn' somewhere deep in e.g. ::SQLMaker
would *not* have been detected.

Also fix improperly applied C-ism: the following decidedly does not DTRT

 do 1 while { ... }

I never noticed this being a problem until a fatfingered `>&1` turned into
a `>1`, which in turn created a file named 1 in the current directory with
garbage in it, which *in turn* the `do 1 ...` tried to execute. Sigh...