validate: launcher: Add some missing env variables in command to launch test

validate/launcher/apps/gstcheck.py

@@ -64,6 +64,7 @@ class MesonTest(Test):
         # No reason to fork since we are launching
         # each test individually
         env['CK_FORK'] = 'no'
+        self.add_env_variable('CK_FORK', 'no')
         for var, val in self.child_env.items():
             self.add_env_variable(var, val)
 

validate/launcher/baseclasses.py

@@ -154,7 +154,7 @@ class Test(Loggable):
             if res:
                 res += " "
             value = self.proc_env.get(var, None)
-            if value:
+            if value is not None:
                 res += "%s='%s'" % (var, value)
 
         return res