chore: bump awsebscsiprovisioner to chart 0.3.8 (#273)

[joejulian]

What type of PR is this?

Bug

What this PR does/ why we need it:

Enables cleanupVolumeSnapshotCRDV1alpha1 by default.

This makes upgrade automatic without manual steps listed in #244 .

Which issue(s) this PR fixes:

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[awsebscsiprovisioner] The manual steps to upgrade the snapshot APIs from v1alpha1 to v1beta1 is no longer required. It has been automated in the chart CRD install hook by default. If you do not want that default behavior of cleaning up v1alpha1 snapshot CRDs, you can set `cleanupVolumeSnapshotCRDV1alpha1` to `false` and follow the instructions for upgrading to Kubernetes `1.17`.

Checklist

• The commit message explains the changes and why are needed.
• The code builds and passes lint/style checks locally.
• The relevant subset of integration tests pass locally.
• The core changes are covered by tests.
• The documentation is updated where needed.

[joejulian]

Manually tested. The test infrastructure is broken when merging to anything but master. I'm merging as-is.