Remove extra blank line from seed output.

This is a follow up to #1761.

The seed output had two new lines, which worked well
at the end (since we want a blank line after our
output) but it looked funny for the new seed notification
at the start.

For comparison, here's what the output used to look like:

```
Run options:
  include {:focus=>true}
  exclude {:ruby=>#<Proc:./spec/spec_helper.rb:79>}

All examples were filtered out; ignoring {:focus=>true}
........

Finished in 0.02398 seconds (files took 0.19841 seconds to load)
8 examples, 0 failures

Randomized with seed 64721

```

Here's what it looks like currently:

```
Run options:
  include {:focus=>true}
  exclude {:ruby=>#<Proc:./spec/spec_helper.rb:79>}

All examples were filtered out; ignoring {:focus=>true}

Randomized with seed 51597

........

Finished in 0.01477 seconds (files took 0.12285 seconds to load)
8 examples, 0 failures

Randomized with seed 51597

```

And here's what it looks like after the changes in this PR:

```
Run options:
  include {:focus=>true}
  exclude {:ruby=>#<Proc:./spec/spec_helper.rb:79>}

All examples were filtered out; ignoring {:focus=>true}

Randomized with seed 11891
........

Finished in 0.01435 seconds (files took 0.12004 seconds to load)
8 examples, 0 failures

Randomized with seed 11891

```