tutorials: Clean up geometry resources

A surface geometry file should be stored in
$FOAM_TUTORIALS/resources/geometry if it is used in multiple cases,
otherwise it should be stored locally to the case. This change enforces
that across all tutorials.

tutorials/mesh/foamyHexMesh/blob/Allclean

@@ -8,8 +8,6 @@ cleanCase
 
 rm -rf 0 > /dev/null 2>&1
 
-rm -rf constant/triSurface/blob.stl.gz > /dev/null 2>&1
-
 rm -rf constant/cellAlignments > /dev/null 2>&1
 rm -rf constant/targetCellSize > /dev/null 2>&1
 rm -rf constant/internalDelaunayVertices > /dev/null 2>&1