Use new Python 3.12 f-string syntax

Now that we have updated this project to use Python 3.12 (#124), all multi-line f-strings should be updated to use the new syntax.

For example:

```python
my_var: str = (
f"""This is a {
random.choice("good", "amazing", "wonderful")
}. My next random number will be provided below in due course: {
random.choice(
999_999_999_999_999,
420,
10,
0
)
if random.randint(0, 101) == 69
else random.random()
}"""
)
```

Would be changed to:

```python
my_var: str = (
f"This is a {random.choice("good", "amazing", "wonderful")}. "
"My next random number will be provided below in due course: "
f"{
random.choice(
999_999_999_999_999,
420,
10,
0
)
if random.randint(0, 101) == 69
else random.random()
}"
)
```

(I am aware that this example can be simplified on to a single line without the line-length being exceeded, however this is just an example. Use the shown changes to help when the changed lines *do* exceed the maximum allowed line-length.)