Stack's support of detailed-0.9 test type appears to be broken

[qrilka]

General summary/comments (optional)

Stack claimed to support detailed-0.9 test suite type starting with #1447
It looks that it got broken somehow, I found it while trying to build Stackage snapshot with Stack.

Steps to reproduce

1. Clone https://github.com/michaxm/test-detailed-example which was the original minimal example for this feature (from stack test with detailed-0.9 fails (executable not found) #1429)
2. Run command stack test.

Expected

Test succeeds.

Actual

Running test hangs indefinitely.

Example Stack log lines before it stalls:

Linking .stack-work/dist/x86_64-linux-tinfo6/Cabal-1.22.4.0/build/test-detailed-example-testStub/test-detailed-example-testStub ...
test-detailed-example-0.1.0.0: copy/register
Installing library in
/home/qrilka/ws/h/test-detailed-example/.stack-work/install/x86_64-linux-tinfo6/lts-3.14/7.10.2/lib/x86_64-linux-ghc-7.10.2/test-detailed-example-0.1.0.0-00o8EUyMcEg219fUJPx6Ed
Registering test-detailed-example-0.1.0.0...
test-detailed-example-0.1.0.0: test (suite: test-detailed-example-test)
            
Progress 1/2: test-detailed-example-0.1.0.0

Stack version

Tried with versions 1.7.1, 1.9.1, 1.9.3

Method of installation

1.9.x:

• Official static binary, downloaded from Github releases
  1.7.1:
• gentoo-haskell Gentoo portage overlay

[snoyberg]

This should be addressed by 75e1091. I've asked @NorfairKing to put together a PR that includes a regression test to catch this in the future.