Use double quotes
This is the first (massive) step towards automated formatting of the backend source code.
When applying black/ruff, the most prevalent issue is the usage of single & double quotes. Let's stick to double quotes as this is the standard in Python world now.
The fixes were generated with ruff using this ruff.toml
file to ONLY generate the quote changes.
line-length = 120
[format]
# Like Black, use double quotes for strings.
quote-style = "double"
[lint]
select = ["Q0"]
ignore = ["F", "E"]
I added flake8-quotes to prevent new single quotes