minor #11812 [HttpFoundation] Improve string values in test codes (DQ…

…NEO)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #11812).

Discussion
----------

[HttpFoundation] Improve string values in test codes

I made the meanings of string literals more clear.

| Q             | A
| ------------- | ---
| Bug fix?      | no,
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | n/a
| License       | MIT
| Doc PR        | n/a

Commits
-------

05f5860 [HttpFoundation] Improve string values in test codes

src/Symfony/Component/HttpFoundation/Tests/RequestTest.php

@@ -200,23 +200,23 @@ public function testCreate()
         $this->assertEquals('test.com:90', $request->getHttpHost());
         $this->assertFalse($request->isSecure());
 
-        $request = Request::create('http://test:test@test.com');
+        $request = Request::create('http://username:password@test.com');
         $this->assertEquals('http://test.com/', $request->getUri());
         $this->assertEquals('/', $request->getPathInfo());
         $this->assertEquals('', $request->getQueryString());
         $this->assertEquals(80, $request->getPort());
         $this->assertEquals('test.com', $request->getHttpHost());
-        $this->assertEquals('test', $request->getUser());
-        $this->assertEquals('test', $request->getPassword());
+        $this->assertEquals('username', $request->getUser());
+        $this->assertEquals('password', $request->getPassword());
         $this->assertFalse($request->isSecure());
 
-        $request = Request::create('http://testnopass@test.com');
+        $request = Request::create('http://username@test.com');
         $this->assertEquals('http://test.com/', $request->getUri());
         $this->assertEquals('/', $request->getPathInfo());
         $this->assertEquals('', $request->getQueryString());
         $this->assertEquals(80, $request->getPort());
         $this->assertEquals('test.com', $request->getHttpHost());
-        $this->assertEquals('testnopass', $request->getUser());
+        $this->assertEquals('username', $request->getUser());
         $this->assertSame('',$request->getPassword());
         $this->assertFalse($request->isSecure());