Final marijuana decriminalization analysis refinements

Context

The medical marijuana analysis is looking nice, but there are a few ways in which it could be improved before we move on.

[x] Create a new file for these operations. Give it a specific name, like Pittsburgh, PA Marijuana Decriminalization analysis 2017–2023 and make sure it's in the analysis folder
- keep the old file for now; maps are still in progress. The old one can be deleted later.
[x] Remove all visualizations, except:
- the final 5
- 51: total arrests and citations by zone 2023
- 84 and 95: total arrests and citations by race and year
[x] remove the final pie chart (nearly the same as the previous one)
[x] for the remaining pie chart, slightly tweak the labels for specificity: Multiple offense arrest Single offense arrest Citation
[x] for the same chart, change the title for specificity: Proportion of marijuana-related offenses 2017–2023
[x] for the double line plot, a specific title would be: Marijuana Arrests and Citations by Year
[x] remove data frames and transformations which were only generated to make those visualizations which were removed
[x] optional: is there a way to remove or truncate the table previews every time a dataframe is made? They take up a lot of space. 3 lines would be sufficient; many of them don't need to be there at all. If this isn't easy to do, don't worry about it!
[x] nice: make the colors shades of red, instead of blue (bright, tomato red for the biggest areas or bars; lighter or darker shades for the other bars)

[ ] Copy the mapping cells and requirements to the file added in the above PR ("Pittsburgh, PA Marijuana Decrim...")
[ ] remove the old MJ Graphs and MJ Maps files, as well as the fall 2024 analysis template
[ ] Adjust the file tree so it looks like this:
- mj-decriminalization/
- README.md
- analysis/
  - Pittsburgh, PA Marijuana Decrim...ipynb
  - arrest_data_wprdc.csv
  - citation_data_wprdc.csv
  - police_zones.geojson
  - requirements.txt
  - archive/
  - everything else
[ ] be sure the notebook still runs and renders correctly
[ ] Add any files in analysis/ to the index in the README; we need to explain where they came from. The source for all of them is WPRDC.
- the description of the most recent python notebook: "Completed analysis related to the question, in response to questions and feedback from Pittsburgh's Alliance for Police Accountability coalition."