EEVEE Soft shadows were not rendered correctly during viewport
rendering. The reason for this is that during viewport rendering the
shadow buffers were only update once and not per sample. This resulted
that all the samples calculated the same shadow.
This fix moves the call to `EEVEE_shadows_update` from cache finished to
draw scene. This needs to happen before `EEVEE_lightprobes_refresh`.
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D6538
7c9d15fca8