Remove empty line from Dockerfile to prevent WARNING

[mzfr]

There was the empty line between different commands which caused docker to give WARNING. I've removed those.

Also, in my opinion, it would be nice to actually use different RUN for each command rather than having a single RUN for all the commands.

[coveralls]

Pull Request Test Coverage Report for Build 1164

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 77.866%

---

Totals
Change from base Build 1152:	0.0%
Covered Lines:	1372
Relevant Lines:	1762

---

💛 - Coveralls