mavsdk_tests: fix bugs in readyness checks

test/mavsdk_tests/mavsdk_test_runner.py

@@ -154,7 +154,7 @@ def determine_tests(workspace_dir, filter):
 def is_running(process_name):
     for proc in psutil.process_iter(attrs=['name']):
         if proc.info['name'] == process_name:
-            True
+            return True
     return False
 
 
@@ -172,6 +172,7 @@ def is_everything_ready():
         print("PX4 SITL is not built\n"
               "run `PX4_MAVSDK_TESTING=y DONT_RUN=1 "
               "make px4_sitl gazebo mavsdk_tests`")
+        result = False
     if not os.path.isfile('build/px4_sitl_default/mavsdk_tests'):
         print("Test runner is not built\n"
               "run `PX4_MAVSDK_TESTING=y DONT_RUN=1 "