Amend contribution guide

[jamesmbaazam]

In this PR, I add a section to explain what happens after a pull request is submitted. This information might be useful for new contributors. This fixes #404.

In the process of the submitting the PR, some words were picked up by the spelling workflow and added to the wordlist. These can be found here d65b5ef and here 74670b1.

[github-actions]

This is how benchmark results would change (along with a 95% confidence interval in relative change) if d2cd1cd is merged into main:

•   :ballot_box_with_check:default: 46.5s -> 50.4s [-6.74%, +23.65%]
•   :ballot_box_with_check:no_delays: 39.2s -> 40.4s [-12.13%, +18.3%]
•   :ballot_box_with_check:random_walk: 13.1s -> 12.9s [-10.98%, +8.23%]
•   :ballot_box_with_check:stationary: 31.8s -> 30.7s [-10.59%, +3.46%]
•   :ballot_box_with_check:uncertain: 45.7s -> 48.9s [-7.07%, +21.12%]
  Further explanation regarding interpretation and methodology can be found in the documentation.

[sbfnk]

Thanks! A few suggested edits for clarit.

[jamesmbaazam]

Thanks, Seb. I have committed the changes.

[github-actions]

This is how benchmark results would change (along with a 95% confidence interval in relative change) if fd7c63a is merged into main:

•   :ballot_box_with_check:default: 1.12m -> 1.14m [-8.96%, +12.66%]
•   :ballot_box_with_check:no_delays: 57.1s -> 58.6s [-15.53%, +20.8%]
•   :ballot_box_with_check:random_walk: 17.2s -> 19.5s [-10.33%, +37.99%]
•   :ballot_box_with_check:stationary: 41.5s -> 41.8s [-10.32%, +11.32%]
•   :ballot_box_with_check:uncertain: 1.15m -> 1.08m [-24.63%, +11.3%]
  Further explanation regarding interpretation and methodology can be found in the documentation.

[seabbs]

Note this doesn't update the dev version of the new file with the changes made.