message: integration_tests: fix mission comparison
  We need to set the acceptance radius to something other than NAN.
  Otherwise, NAN gets converted to a default and then fails the validation
  if the mission items are still the same after an upload and download
  cycle.
diff: @@ -103,7 +103,7 @@ void test_mission(
  60.0f,
  NAN,
  Mission::MissionItem::CameraAction::None,
  - NAN));
  + 0.5f));
  mission_plan.mission_items.push_back(add_mission_item(
  47.398241338125118,
  @@ -115,7 +115,7 @@ void test_mission(
  -60.0f,
  5.0f,
  Mission::MissionItem::CameraAction::TakePhoto,
  - NAN));
  + 4.0f));
  mission_plan.mission_items.push_back(add_mission_item(
  47.398139363821485,
  @@ -127,7 +127,7 @@ void test_mission(
  0.0f,
  NAN,
  Mission::MissionItem::CameraAction::StartVideo,
  - NAN));
  + 4.0f));
  mission_plan.mission_items.push_back(add_mission_item(
  47.398058617228855,
  @@ -139,7 +139,7 @@ void test_mission(
  30.0f,
  NAN,
  Mission::MissionItem::CameraAction::StopVideo,
  - NAN));
  + 0.5f));
  mission_plan.mission_items.push_back(add_mission_item(
  47.398100366082858,
  @@ -151,7 +151,7 @@ void test_mission(
  -30.0f,
  NAN,
  Mission::MissionItem::CameraAction::StartPhotoInterval,
  - NAN));
  + 0.5f));
  mission_plan.mission_items.push_back(add_mission_item(
  47.398001890458097,
  @@ -163,7 +163,7 @@ void test_mission(
  0.0f,
  NAN,
  Mission::MissionItem::CameraAction::StopPhotoInterval,
  - NAN));
  + 0.5f));
  }
  mission->set_return_to_launch_after_mission(true);
  