message: Fix paths in a quest test and example
  Both hardcoded a path that was not updated during a recent reorganization of the code.
  In addition to fixing the paths, I also added checks that the file actually exists.
diff: @@ -176,8 +176,8 @@ void testContainmentOnRegularGrid(
  new mint::UniformMesh(low, high, gridRes, gridRes, gridRes);
  const int nnodes = umesh->getNumberOfNodes();
  - int* containment = umesh->createField< int >( "containment",
  - mint::NODE_CENTERED );
  + int* containment =
  + umesh->createField< int >( "containment", mint::NODE_CENTERED );
  SLIC_ASSERT( containment != nullptr );
  @@ -400,20 +400,25 @@ int main( int argc, char** argv )
  // STEP 1: Get file from user or use default
  std::string stlFile;
  +
  + // load the file
  + {
  + namespace fs = axom::utilities::filesystem;
  if(hasInputArgs)
  {
  stlFile = std::string( argv[1] );
  }
  else
  {
  - const std::string defaultFileName = "plane_simp.stl";
  - const std::string defaultDir = "src/components/quest/data/";
  -
  - stlFile = utilities::filesystem::joinPath(defaultDir, defaultFileName);
  + const std::string dir = fs::joinPath(AXOM_SRC_DIR, "axom/quest/data");
  + const std::string mesh = "plane_simp.stl";
  + stlFile = fs::joinPath(dir, mesh);
  }
  - stlFile = slam::util::findFileInAncestorDirs(stlFile);
  - SLIC_ASSERT( utilities::filesystem::pathExists( stlFile));
  + // Verify that the mesh file exists
  + SLIC_ERROR_IF( !fs::pathExists( stlFile),
  + fmt::format("Mesh file '{}' does not exist.", stlFile));
  + }
  // STEP 2: read mesh file
  SLIC_INFO(fmt::format("\n\t{:*^80}"," Loading the mesh "));
  