Fix minor typos in bug_report.md

[jongwooo]

What this PR does / why we need it:

Fix minor typos in .github/ISSUE_TEMPLATE/bug_report.md:

• namepspace -> namespace
• appnnamespace -> appnamespace

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• CVE Report (Scanner found CVE and adding report)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation only

Which issue/s this PR fixes

None

How Has This Been Tested?

None

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added unit and/or e2e tests to cover my changes.
• All new and existing tests passed.

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[k8s-ci-robot]

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[cpanato]

Thanks
/approve

[strongjz]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato, jongwooo, strongjz

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• OWNERS [cpanato,strongjz]

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