Todd Gamblin 740f8fe1a9 bugfix: spack test should not output [+] for mock installs (#15609) ...

`spack test` has a spurious '[+] ' in the output:

```
lib/spack/spack/test/install.py .........[+] ......
```

Output is properly suppressed:

```
lib/spack/spack/test/install.py ...............
```

2020-04-15 14:30:58 -07:00

..

spack

bugfix: spack test should not output [+] for mock installs (#15609)

2020-04-15 14:30:58 -07:00