Update release deployment docs

[marlowpayne]

Changes

• Releases should merge to master, then merge master into develop
• Add clarity to merging commands to ensure that local code isn't outdated
• Astro's release doc is long and has special cases. Use code style's release doc as reference instead
• Remove some redundancy around creating GitHub releases

How to Test

• Proofread doc changes

Todos:

• Update Release Deployment doc's diagrams as necessary
• +1

[marlowpayne]

Added these extra steps to ensure that branches are up to date before merging.

[jansepar]

We should be adding a point that "When merging a hotfix into master, and then master into develop, master should also be merged into any currently open release branches."

[highruned]

Nothing blocking from me. Looks solid! 👍

[jeremywiebe]

It looks like our diagrams for the Release Deployment workflow are still showing merging from the release/hotfix into develop. Maybe we put that on a TODO list, but it's certainly affected by the changes to this PR.

[mikenikles]

@jeremywiebe Do you know who owns the image files for the diagrams? I only see png files and can't edit them to reflect the changes in this PR.