ADD support for new coinbase CSV format (V4)

[Griffsano]

The Coinbase CSV format changed (again) somewhere in 2023 or 2024. I noticed the following changes with respect to the previous version:

• No header line ("You can use this transaction report to inform your likely tax obligations...") and change in number of empty lines
• Number of columns changed to 11, with a newly introduced "ID" column (not used for tax calculation)
• The following columns now contain the Euro symbol: Price at transaction, subtotal, total, fees
• The following columns now contain negative numbers (if applicable): Quantity transacted, subtotal, total
• The UTC time format changed

I hope this PR covers all changes in the CSV format. However, my Coinbase export is pretty short with a limited number of transaction types. Therefore, there may be further code changes necessary that are not covered by this PR.

[provinzio]

Hey @Griffsano and happy to new year. Thanks for the contribution. Looks good to me so far. We can merge this and edit as soon as someone has a bigger file with more transaction data.

Please check the pipeline errors before I merge.

Edit: Sorry, I fucked up the linter warnings and haven't noticed so far... I fixed the warning.

[Griffsano]

Happy new year to you too @provinzio and thanks for merging!