Revert change to mirror threshold

[howardjohn]

What type of PR is this?

/area conformance-test

What this PR does / why we need it:
Reverts part of #3508. This was a new change in 1.3

See #3708; Envoy impl cannot meet this fine grain threshold.

Which issue(s) this PR fixes:

Fixes #

Does this PR introduce a user-facing change?:

NONE

[howardjohn]

cc @LiorLieberman

[robscott]

Thanks @howardjohn!

/lgtm
/approve

Will also add a brief hold if anyone else wants to chime in, otherwise feel free to remove in ~24h

[robscott]

/hold

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: howardjohn, robscott

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• conformance/OWNERS [howardjohn,robscott]

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[LiorLieberman]

Thanks,
/lgtm

/cc @mhofstetter

[k8s-ci-robot]

@LiorLieberman: GitHub didn't allow me to request PR reviews from the following users: mhofstetter.

Note that only kubernetes-sigs members and repo collaborators can review this PR, and authors cannot review their own PRs.

In response to this:

Thanks,
/lgtm

/cc @mhofstetter

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[LiorLieberman]

/unhold