docs: improve environment variables section

[TC-MO]

remove outdated screenshots and instructions
make sure instructions reflect current state
reformat md table to be more readable
change doc structure and logical flow
add admonitions

[janbuchar]

Thanks so much for this! Are there still some internal variables that should be included? Also, we may mention the deprecated forms of some variables, for example APIFY_DEFAULT_DATASET_ID

[TC-MO]

Thanks so much for this! Are there still some internal variables that should be included? Also, we may mention the deprecated forms of some variables, for example APIFY_DEFAULT_DATASET_ID

I kind of hoped the spreadsheet was all that was missing :D

[janbuchar]

Thanks so much for this! Are there still some internal variables that should be included? Also, we may mention the deprecated forms of some variables, for example APIFY_DEFAULT_DATASET_ID

I kind of hoped the spreadsheet was all that was missing :D

If you put everything in the spreadsheet into the docs, then yeah, that should do it 🙂 I don't think that for example APIFY_INPUT_SECRETS_PRIVATE_KEY_FILE is in the updated doc though.

[janbuchar]

Good stuff!