ci: Fix failure in unit tests with vs backend

run_unittests.py

@@ -2382,7 +2382,7 @@ class AllPlatformTests(BasePlatformTests):
         self.init(testdir)
         self.run_target('check_exists')
         self.run_target('check-env')
-        self.run_target('dummy.stamp')
+        self.run_target('check-env-ct')
 
     def test_install_introspection(self):
         '''

test cases/common/52 run target/meson.build

@@ -93,7 +93,7 @@ run_target('check-env',
 # Check some string substitutions that has always been done but never documented.
 # Some projects have been relying on this implementation detail. This is
 # documented behaviour since 0.57.1.
-custom_target('dummy.stamp',
+custom_target('check-env-ct',
   command: [find_program('check-env.py'), '@SOURCE_ROOT@', '@BUILD_ROOT@',
             '@CURRENT_SOURCE_DIR@'],
   env: {'MESON_SOURCE_ROOT': meson.source_root(),
@@ -101,5 +101,5 @@ custom_target('dummy.stamp',
         'MESON_SUBDIR': meson.current_source_dir(),
         'MESONINTROSPECT': 'fake value',
         'MY_ENV': '1'},
-  output: 'dummy.stamp',
+  output: 'check-env-ct',
 )