Update an expired certificate within the cert-auth test fixtures

[stevendpclark]

Description

Update an expired certificate within the cert-auth test fixtures, extending it's NotAfter by 25 years to 2050 for now.

TODO only if you're a HashiCorp employee

• Backport Labels: If this fix needs to be backported, use the appropriate backport/ label that matches the desired release branch. Note that in the CE repo, the latest release branch will look like backport/x.x.x, but older release branches will be backport/ent/x.x.x+ent.
  • LTS: If this fixes a critical security vulnerability or severity 1 bug, it will also need to be backported to the current LTS versions of Vault. To ensure this, use all available enterprise labels.
• ENT Breakage: If this PR either 1) removes a public function OR 2) changes the signature
  of a public function, even if that change is in a CE file, double check that
  applying the patch for this PR to the ENT repo and running tests doesn't
  break any tests. Sometimes ENT only tests rely on public functions in CE
  files.
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[github-actions]

CI Results:
All Go tests succeeded! ✅

[github-actions]

Build Results:
All builds succeeded! ✅

[kitography]

LGTM

[sgmiller]

Just so I'm reading this right, you're largely getting rid of expirable test fixtures in favor of cheap EC certs generated at test time?

[sgmiller]

Nice addition!

[stevendpclark]

Just so I'm reading this right, you're largely getting rid of expirable test fixtures in favor of cheap EC certs generated at test time?

Correct, I also find it a bit easier to understand what the test requires this way, instead of various generated static certificates kind of mixed together to force the desired failure.