Tests: Remove unused RunCMake.TransformDepfile files

Remove files missed by commit f0e9d74a2d (cmake_transform_depfile:
Remove unused incomplete vstlog support, 2021-06-02).

Tests/RunCMake/TransformDepfile/deps-unix.tlog.txt

@@ -1,6 +0,0 @@
-^subdir/out1|/home/build/out2
-subdir/in1
-/home/build/in2
-^subdir/out3|/home/build/out4
-subdir/in3
-/home/build/in4

Tests/RunCMake/TransformDepfile/deps-windows.tlog.txt

@@ -1,6 +0,0 @@
-^subdir\out1|C:\build\out2
-subdir\in1
-C:\build\in2
-^subdir\out3|C:\build\out4
-subdir\in3
-C:\build\in4

Tests/RunCMake/TransformDepfile/invalid-tlog-result.txt

@@ -1 +0,0 @@
-2

Tests/RunCMake/TransformDepfile/vstlog.cmake

@@ -1,16 +0,0 @@
-if(EXISTS "${RunCMake_SOURCE_DIR}/${name}.tlog.txt")
-  file(READ "${RunCMake_SOURCE_DIR}/${name}.tlog.txt" expected_contents)
-
-  if(EXISTS "${RunCMake_TEST_BINARY_DIR}/out.tlog")
-    file(READ "${RunCMake_TEST_BINARY_DIR}/out.tlog" actual_contents)
-    if(NOT actual_contents STREQUAL expected_contents)
-      string(REPLACE "\n" "\n  " p_expected_contents "${expected_contents}")
-      string(REPLACE "\n" "\n  " p_actual_contents "${actual_contents}")
-      string(APPEND RunCMake_TEST_FAILED "Expected contents of ${RunCMake_TEST_BINARY_DIR}/out.tlog:\n  ${p_expected_contents}\nActual contents:\n  ${p_actual_contents}")
-    endif()
-  else()
-    string(APPEND RunCMake_TEST_FAILED "${RunCMake_TEST_BINARY_DIR}/out.tlog should exist\n")
-  endif()
-elseif(EXISTS "${RunCMake_TEST_BINARY_DIR}/out.tlog")
-  string(APPEND RunCMake_TEST_FAILED "${RunCMake_TEST_BINARY_DIR}/out.tlog should not exist\n")
-endif()