Remove sub-sub section heading from rendering guide

[dstansby]

Description

The block of text under this heading doesn't refer to time-series data. While it's applicable to time-series data, it's also applicable to 3D volume data, so it seemed easiest just to remove the heading.

Type of change

• Fixes or improves existing content

References

Final checklist:

• My PR is the minimum possible work for the desired functionality
• I have commented my code, particularly in hard-to-understand areas
• I have added alt text to new images included in this PR

[psobolewskiPhD]

Huh, that heading is kinda oddly out of place isn't it.
Thanks for catching this.

Small aside--not blocking, just came to mind: @andy-sweet do we need to update any of this for the new async? If so, should we make an issue to track?

[andy-sweet]

Small aside--not blocking, just came to mind: @andy-sweet do we need to update any of this for the new async? If so, should we make an issue to track?

Yes, you're right. I added an issue to describe some thoughts and ideas there: #237