Periodic Prow Job to Update Istio Dependency SHA

[chxchx]

An example PR created is istio/istio#588

Notice that it reads SHA from stable branch of each dependency. For the entire dependency update scheme to be automated, it also needs the fast-forward jobs that move stable up-to-date with master, which will be done in another PR shortly after.

Release note:

NONE

[chxchx]

/assign @sebastienvas
/assign @yutongz
PTAL

[sebastienvas]

/lgtm
/approve

[istio-merge-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: sebastienvas

The full list of commands accepted by this bot can be found here.

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• prow/OWNERS [sebastienvas]

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[istio-merge-robot]

/test all [submit-queue is verifying that this PR is safe to merge]

[istio-merge-robot]

Automatic merge from submit-queue

[istio-testing]

@chxchx: I updated Prow config for you!.

In response to this:

An example PR created is istio/istio#588

Notice that it reads SHA from stable branch of each dependency. For the entire dependency update scheme to be automated, it also needs the fast-forward jobs that move stable up-to-date with master, which will be done in another PR shortly after.

Release note:

NONE

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