fix(rt): generate proxy idp eppns from einfra idp identities

Description

fix(rt): generate proxy idp eppns from einfra idp identities

We plan to remove all old Metacentrum IdP identities hence we must use different identity as a source when generating proxy IdP EPPN.

How to test

Generate data using old/new script version. Identities login@einfra.cesnet.cz should be present in both outputs. login should match einfra login in both cases. New users (without old login@meta.cesnet.cz identity) should have new identity generated (hence outputs are not really the same, there will be such identities added).

Author's checklist

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• This MR has been tested or does not change functionality
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Reviewer's checklist

• This MR has been tested or does not change functionality
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Other information

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Related issues

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