I did a languages degree and in my final year worked a 20 hour week at a local business doing admin and web design. I scraped a 2:1. In hindsight, I'm not sure of the value my degree has in terms of my career but the work experience was vital.
I guess it depends what you want to do next. If you wish to use your degree for example as a translator, you should focus on your studies. If you're looking at something less related, like a comms post then keep the job.
In the past few months I have recruited two junior level positions and when looking at candidates, their degree is of minor interest. It's generally a case of check to see if they have at least a 2:2 in any discipline.
Mostly I'm looking at their work experience, because actually your degree does nothing to prepare you for the workplace unless it's something highly specialised/vocational.