chore(backend): Fixed namespace in job creation

[hbelmiro]

When creating recurring runs, the ScheduledWorkflow CR is created with no namespace set.
This PR changes the CreateJob method so the namespace is set in the Job before creating the ScheduledWorkflow.

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[google-oss-prow]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[VaniHaripriya]

/lgtm

[franciscojavierarceo]

lgtm

[hbelmiro]

@HumairAK can you PTAL?

[rimolive]

/lgtm

[HumairAK]

/lgtm
/approve

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: franciscojavierarceo, HumairAK

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