Add case for when user agent is nil

[BrianKopp]

This PR simply adds a check to protect against a nil user agent in the same site tests, as pointed out here.

What this PR does / why we need it:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Which issue/s this PR fixes

How Has This Been Tested?

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added tests to cover my changes.
• All new and existing tests passed.

[k8s-ci-robot]

Hi @BrianKopp. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[aledbf]

/ok-to-test

[aledbf]

/retest

[codecov-io]

Codecov Report

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The diff coverage is n/a.

@@            Coverage Diff            @@
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  Coverage          ?   58.68%           
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  Files             ?       88           
  Lines             ?     6850           
  Branches          ?        0           
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  Hits              ?     4020           
  Misses            ?     2390           
  Partials          ?      440

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[aledbf]

/lgtm
/approve

[aledbf]

@BrianKopp thanks!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aledbf, BrianKopp

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• OWNERS [aledbf]

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[aledbf]

/retest