Run tests with two data layer implementations

[irar2]

What type of PR is this?
/kind cleanup

What this PR does / why we need it:
This PR changes the tests to run with both pkg/epp/backend/metrics and pkg/epp/datalayer.
Which issue(s) this PR fixes:

Fixes #1877

Does this PR introduce a user-facing change?:

NONE

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[k8s-ci-robot]

Hi @irar2. Thanks for your PR.

I'm waiting for a github.com 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.

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[shmuelk]

/lgtm

[shmuelk]

/ok-to-test

[shmuelk]

/retest

[irar2]

/retest

[shmuelk]

/retest

[nirrozenbaum]

/lgtm
/approve

Thanks!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: irar2, nirrozenbaum

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