update rust version in docker image

[adriangb]

#758 (comment)

[adriangb]

cc @levkk

[adriangb]

I tested this and it built locally. That said it did also build before this change but I think it was because it was defaulting to this version due to lack of pin.

[adriangb]

Seems like this didn't work: https://github.com/postgresml/pgcat/actions/runs/9648450240/job/26609660013

There must be some sort of CI cache going on.

[lobaorn]

Hi @adriangb @levkk it is not a CI cache, it is the checkout action version in the workflow. See:

actions/checkout#1464

actions/checkout#1596

actions/checkout#1674

I believe that by just upgrading the workflow version it should be fine.

Edit: I went to check, it was not because of what I said, that part was solely a warning still, I do not think it will solve it.

Edit2: I guess it is because of this file that was not updated since https://github.com/postgresml/pgcat/blob/main/Dockerfile.ci