Tests: Updated test message for Directory Not Found

Tests: Updated test message for Directory Not Found

Added more Geometry Node tests

* Attributes
* Utilities
* Volume

Test folder located in `libtestsmodelinggeometry_nodes`
It contains around 34 new tests.
* attribute clamp + other attribute nodes
* Curve Primitive nodes
* Mesh Primitive nodes
* delete geometry
* convex hull
* subdivision surface
* boolean intersect
* boolean diff
* volume to mesh

Reviewed By: zazizizou, JacquesLucke

Differential Revision: https://developer.blender.org/D12250

Using relative threshold for floats in mesh comparison

Changes the threshold comparison from absolute to relative.
Removes threshold for MLoopCol comparison.

Adds a compare relative threshold function.

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D12273

Add cutom data color property for mesh comparison

Add color data type comparison for meshes, adding it as
part of comparing meshes with geometry nodes applied.

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D12192

Refactor: Custom data comparison in meshes

Added the comparison of non-generic attributes with generic
attributes in the same loop to avoid issues with different
order in layer->types of the two meshes.

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D12149

Refactor: Custom data comparison in meshes

Added the comparison of non-generic attributes with generic
attributes in the same loop to avoid issues with different
order in layer->types of the two meshes.

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D12149

Add custom data comparison for generic attributes

Generic attributes CD_PROP_* comparison is added in customdata_compare
Checks for built-in as well as user created attributes.

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D12137

Add custom data comparison for generic attributes

Generic attributes CD_PROP_* comparison is added in customdata_compare
Checks for built-in as well as user created attributes.

Reviewed By: JacquesLucke

Differential Revision: https://developer.blender.org/D12137

Regression Testing: Running tests based on blend files

Runs tests based on blend files with minimum python interaction.
Developed as part of GSoC 2021 - Regression Testing of Geometry Nodes.
Earlier, tests were built from scratch by adding a modifier/operation
from the Python API.
Now, tests can also be created inside blender and are compared using
Python script.

Features: Automatically adding expected object if it doesn't exist.
This patch adds tests for the following Geometry Nodes category:
* Curves
* Geometry
* Mesh
* Points

The implemented UML diagram for refactoring of mesh test framework.
{F10225906}

Technical Changes:
SpecMeshTest: It adds the modifier/operation based on the Spec provided.
BlendFileTest: It applies already existing modifier/operation from the blend file.

Test folders hierarchy with tests. This folder should be extracted to `libtestsmodeling`
{F10240651}
Note: The `geometry_nodes` folder might lie under another `geometry_nodes` folder while extracting, please double check. Use the inner-most one.
The hierarchy should be:
-`libtestsmodelinggeometry_nodesmesh`
-`libtestsmodelinggeometry_nodespoints`
and so on.

* From `ctest` the tests should be run as `ctest -R geo_node -C [Configuration]` on Windows.
* Each single test can be run with its entire name e..g `ctest -R geo_node_geometry_join_geometry`.(just an example). Run `ctest -N -R geo_node` to see all tests.
* From blender, the tests can be run `blender -b pathtoblendfile --python pathtogeo_node_test.py`

Reviewed By: zazizizou, JacquesLucke

Differential Revision: https://developer.blender.org/D11611