We repeat many lines of setup code in the two http tests,
and further tests would need to repeat it again. Let's
factor this out into a function.
Incidentally, this also fixes an unlikely bug: if the httpd
root path contains a double-quote, our test_when_finished
would barf due to improper quoting (we escape the embedded
quotes, but not the $, meaning we expand the variable before
the eval).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>