test: add extra space in pseudo-tty test failure output

[Ayase-252]

It adds a extra space between test suite name and the failure reason when a test in pseduo-tty fails. It imporoves the readablity of failure message.

Considering test case

// test/pesudo-tty/test-of-course-it-will-fail-line.js
'use strict'

process.stdout.write("no, no")

and expected output

of course, it fails intentionally
I have two line

Before the change, the test failure is shown as

Before
[00:00|%   0|+   0|-   0]: release test-of-course-it-will-fail-linelength differs.
expect=2
actual=1
patterns:
pattern = ^of\ course\,\ it\ fails\ intentionally$
pattern = ^I\ have\ two\ line$
outlines:
outline = no, no
=== release test-of-course-it-will-fail-line ===                   
Path: pseudo-tty/test-of-course-it-will-fail-line
no, no
Command: /System/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python /Users/qingyudeng/projects/node/test/pseudo-tty/pty_helper.py out/Release/node /Users/qingyudeng/projects/node/test/pseudo-tty/test-of-course-it-will-fail-line.js
[00:00|% 100|+   0|-   1]: Done  

After the change, it will be shown as

[00:00|%   0|+   0|-   0]: release test-of-course-it-will-fail-line length differs.
expect=2
actual=1
patterns:
pattern = ^of\ course\,\ it\ fails\ intentionally$
pattern = ^I\ have\ two\ line$
outlines:
outline = no, no
=== release test-of-course-it-will-fail-line ===                   
Path: pseudo-tty/test-of-course-it-will-fail-line
no, no
Command: /System/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python /Users/qingyudeng/projects/node/test/pseudo-tty/pty_helper.py out/Release/node /Users/qingyudeng/projects/node/test/pseudo-tty/test-of-course-it-will-fail-line.js
[00:00|% 100|+   0|-   1]: Done  

Also, it happens when match failure occurs

Before

[00:00|%   0|+   0|-   0]: release test-of-course-it-will-failmatch failed
line=0
expect=^of\ course\,\ it\ fails\ intentionally$
actual=no, no
=== release test-of-course-it-will-fail ===                   
Path: pseudo-tty/test-of-course-it-will-fail
no, no
Command: /System/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python /Users/qingyudeng/projects/node/test/pseudo-tty/pty_helper.py out/Release/node /Users/qingyudeng/projects/node/test/pseudo-tty/test-of-course-it-will-fail.js

After

[00:00|%   0|+   0|-   0]: release test-of-course-it-will-fail match failed
line=0
expect=^of\ course\,\ it\ fails\ intentionally$
actual=no, no
=== release test-of-course-it-will-fail ===                   
Path: pseudo-tty/test-of-course-it-will-fail
no, no
Command: /System/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python /Users/qingyudeng/projects/node/test/pseudo-tty/pty_helper.py out/Release/node /Users/qingyudeng/projects/node/test/pseudo-tty/test-of-course-it-will-fail.js
[00:00|% 100|+   0|-   1]: Done  

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/37118/

[aduh95]

Landed in a59b6a1