test: remove stray copyright notices

Commit 3e1b1dd ("Remove excessive copyright/license boilerplate") left
in a few lines of boilerplate here and there.  This commit removes them.

PR-URL: #1793
Reviewed-By: Trevor Norris <trev.norris@gmail.com>

test/message/eval_messages.js

@@ -1,5 +1,4 @@
 'use strict';
-// USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 var common = require('../common');
 var assert = require('assert');

test/message/stdin_messages.js

@@ -1,5 +1,4 @@
 'use strict';
-// USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 var common = require('../common');
 var assert = require('assert');

test/parallel/test-event-emitter-listeners-side-effects.js

@@ -1,5 +1,4 @@
 'use strict';
-// USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 var common = require('../common');
 var assert = require('assert');

test/parallel/test-event-emitter-listeners.js

@@ -1,5 +1,4 @@
 'use strict';
-// USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 var common = require('../common');
 var assert = require('assert');