…r to v0.3.1

The seaweedfs COSI driver shipped at v0.1.2 hardcodes read-write S3
actions (Read, Write, List, Tagging) for every BucketAccess and never
reads the accessPolicy parameter. The chart already defines a -readonly
BucketAccessClass carrying parameters.accessPolicy: readonly, but v0.1.2
ignores it, so a credential meant to be read-only can still write
(upload and delete) objects.

Bump the driver to v0.3.1, which honours accessPolicy: readonly by
issuing Read,List-only credentials (read-write and the empty default
stay Read,Write,List,Tagging). The override lives in the package
values.yaml rather than the vendored chart so it survives make update;
the sister extra/seaweedfs chart already runs v0.3.1.

Assisted-By: Claude <noreply@anthropic.com>
Signed-off-by: Aleksei Sviridkin <f@lex.la>
(cherry picked from commit 0c6426f)