Allow using fusermount3

[ktock]

Fixes #340

go-fuse already supports fusermount3: hanwen/go-fuse@934a183

[ktock]

CI failure of Tests / K3SArgoWorkflow looks unrelated to the change. (ref: #971)

https://github.com/containerd/stargz-snapshotter/actions/runs/3369778264/jobs/5589855174#step:8:13

 result to /home/runner/work/stargz-snapshotter/stargz-snapshotter/argo-workflow//result.json
--2022-11-01 13:33:27--  https://raw.githubusercontent.com/argoproj/argo-workflows/stable/manifests/quick-start-minimal.yaml
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 185.199.109.133, 185.199.108.133, 185.199.110.133, ...
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|185.199.109.133|:443... connected.
HTTP request sent, awaiting response... 404 Not Found
2022-11-01 13:33:27 ERROR 404: Not Found.