[test] Remove request host header preservation

Already tested by PSR7 test suite compliance

test/RequestTest.php

@@ -263,128 +263,6 @@ public function testSettingNewUriResetsRequestTarget()
         $newRequest = $request->withUri(new Uri('http://mwop.net/bar/baz'));
     }
 
-    /**
-     * @group 39
-     */
-    public function testGetHeadersContainsHostHeaderIfUriWithHostIsPresent()
-    {
-        $request = new Request('http://example.com');
-        $headers = $request->getHeaders();
-        $this->assertArrayHasKey('Host', $headers);
-        $this->assertContains('example.com', $headers['Host']);
-    }
-
-    /**
-     * @group 39
-     */
-    public function testGetHeadersContainsNoHostHeaderIfNoUriPresent()
-    {
-        $request = new Request();
-        $headers = $request->getHeaders();
-        $this->assertArrayNotHasKey('Host', $headers);
-    }
-
-    /**
-     * @group 39
-     */
-    public function testGetHeadersContainsNoHostHeaderIfUriDoesNotContainHost()
-    {
-        $request = new Request(new Uri());
-        $headers = $request->getHeaders();
-        $this->assertArrayNotHasKey('Host', $headers);
-    }
-
-    /**
-     * @group 39
-     */
-    public function testGetHostHeaderReturnsUriHostWhenPresent()
-    {
-        $request = new Request('http://example.com');
-        $header = $request->getHeader('host');
-        $this->assertEquals(['example.com'], $header);
-    }
-
-    /**
-     * @group 39
-     */
-    public function testGetHostHeaderReturnsEmptyArrayIfNoUriPresent()
-    {
-        $request = new Request();
-        $this->assertSame([], $request->getHeader('host'));
-    }
-
-    /**
-     * @group 39
-     */
-    public function testGetHostHeaderReturnsEmptyArrayIfUriDoesNotContainHost()
-    {
-        $request = new Request(new Uri());
-        $this->assertSame([], $request->getHeader('host'));
-    }
-
-    /**
-     * @group 39
-     */
-    public function testGetHostHeaderLineReturnsUriHostWhenPresent()
-    {
-        $request = new Request('http://example.com');
-        $header = $request->getHeaderLine('host');
-        $this->assertContains('example.com', $header);
-    }
-
-    /**
-     * @group 39
-     */
-    public function testGetHostHeaderLineReturnsNullIfNoUriPresent()
-    {
-        $request = new Request();
-        $this->assertEmpty($request->getHeaderLine('host'));
-    }
-
-    /**
-     * @group 39
-     */
-    public function testGetHostHeaderLineReturnsNullIfUriDoesNotContainHost()
-    {
-        $request = new Request(new Uri());
-        $this->assertEmpty($request->getHeaderLine('host'));
-    }
-
-    public function testPassingPreserveHostFlagWhenUpdatingUriDoesNotUpdateHostHeader()
-    {
-        $request = (new Request())
-            ->withAddedHeader('Host', 'example.com');
-
-        $uri = (new Uri())->withHost('www.example.com');
-        $new = $request->withUri($uri, true);
-
-        $this->assertEquals('example.com', $new->getHeaderLine('Host'));
-    }
-
-    public function testNotPassingPreserveHostFlagWhenUpdatingUriWithoutHostDoesNotUpdateHostHeader()
-    {
-        $request = (new Request())
-            ->withAddedHeader('Host', 'example.com');
-
-        $uri = new Uri();
-        $new = $request->withUri($uri);
-
-        $this->assertEquals('example.com', $new->getHeaderLine('Host'));
-    }
-
-    public function testHostHeaderUpdatesToUriHostAndPortWhenPreserveHostDisabledAndNonStandardPort()
-    {
-        $request = (new Request())
-            ->withAddedHeader('Host', 'example.com');
-
-        $uri = (new Uri())
-            ->withHost('www.example.com')
-            ->withPort(10081);
-        $new = $request->withUri($uri);
-
-        $this->assertEquals('www.example.com:10081', $new->getHeaderLine('Host'));
-    }
-
     public function headersWithInjectionVectors()
     {
         return [