feat: add VSI PathSpecificOptions and VSI Credentials

[oleksii-leonov]

Add FFI mappings for:

• VSISetPathSpecificOption
• VSIClearPathSpecificOptions
• VSIGetPathSpecificOption
• VSISetCredential
• VSIClearCredentials
• VSIGetCredential

[turboladen]

Looks like we need to update our CI workflow to get it running again.