chore: update containerd/continuity to latest version

[mfridman]

This PR does not attempt to update all dependencies, only containerd/continuity.

go get -u github.com/containerd/continuity@latest
go mod tidy
go mod verify

Why this one specifically? Because older versions of this package used a jwt package that has a "high severity" CVE (not really "high severity" in my opinion, but whatever).

By bumping this dependency (which hopefully doesn't break anything) will avoid dependants of ory/dockertest having to deal with this issue. An example pressly/goose#330

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (v3@cfab898). Click here to learn what that means.
The diff coverage is n/a.

@@          Coverage Diff          @@
##             v3     #352   +/-   ##
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  Coverage      ?   53.59%           
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  Files         ?        1           
  Lines         ?      334           
  Branches      ?        0           
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  Hits          ?      179           
  Misses        ?      118           
  Partials      ?       37           

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[mfridman]

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