Fix minor syntax issue

Hello,

Thanks you for sharing your great buildpack, but I faced an issue when pushing on Heroku:
```
-----> Fetching custom git buildpack... done
-----> Multipack app detected
=====> Downloading Buildpack: https://github.com/abhishekmunie/heroku-buildpack-git.git
=====> Detected Framework: Static
-----> Downloading Git 1.8.1.4...        done.
/tmp/buildpack2dxCF/bin/compile: line 34: syntax error in conditional expression: unexpected token `;'
 !     Heroku push rejected, failed to compile Multipack app
```
You just forgot a space :)