Fixer tests: move fixtures

Move the test fixtures for the `GenerateDiffTest` to a subdirectory.

Author: jrfnl

…es/GenerateDiffTest-BlankLinesAtEnd.diff …st/GenerateDiffTest-BlankLinesAtEnd.difftests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtEnd.diff renamed to tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtEnd.diff tests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtEnd.diff renamed to tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtEnd.diff

@@ -1,4 +1,4 @@
---- tests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtEnd.inc
+--- tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtEnd.inc
 +++ PHP_CodeSniffer
 @@ -5,7 +5,3 @@
  if ($var) {

…res/GenerateDiffTest-BlankLinesAtEnd.inc …est/GenerateDiffTest-BlankLinesAtEnd.inctests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtEnd.inc renamed to tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtEnd.inc tests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtEnd.inc renamed to tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtEnd.inc

@@ -1,4 +1,4 @@
---- tests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtStart.inc
+--- tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtStart.inc
 +++ PHP_CodeSniffer
 @@ -1,6 +1,3 @@
 -

…/GenerateDiffTest-BlankLinesAtStart.diff …/GenerateDiffTest-BlankLinesAtStart.difftests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtStart.diff renamed to tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtStart.diff tests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtStart.diff renamed to tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtStart.diff

@@ -1,4 +1,4 @@
---- tests/Core/Fixer/Fixtures/GenerateDiffTest-LineAdded.inc
+--- tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-LineAdded.inc
 +++ PHP_CodeSniffer
 @@ -1,4 +1,5 @@
  <?php

…s/GenerateDiffTest-BlankLinesAtStart.inc …t/GenerateDiffTest-BlankLinesAtStart.inctests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtStart.inc renamed to tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtStart.inc tests/Core/Fixer/Fixtures/GenerateDiffTest-BlankLinesAtStart.inc renamed to tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-BlankLinesAtStart.inc

@@ -1,4 +1,4 @@
---- tests/Core/Fixer/Fixtures/GenerateDiffTest-LineRemoved.inc
+--- tests/Core/Fixer/Fixtures/GenerateDiffTest/GenerateDiffTest-LineRemoved.inc
 +++ PHP_CodeSniffer
 @@ -4,5 +4,4 @@