dt/config_test: Add OIDC_ALLOW_LIST

[oleiman]

Fixes CORE-7816

Allow logs of the form 'security - .* - Error updating...', which will appear when the configured OIDC endpoint is not available.

This is benign in cases like the test for valid cluster config settings, where OIDC functionality is not the subject of the test.

Backports Required

• [ ] none - not a bug fix
• [ ] none - this is a backport
• [ ] none - issue does not exist in previous branches
• [ ] none - papercut/not impactful enough to backport
• [x] v24.3.x
• [x] v24.2.x
• [x] v24.1.x

Release Notes

• none

[vbotbuildovich]

/backport v24.3.x

[vbotbuildovich]

/backport v24.2.x

[vbotbuildovich]

/backport v24.1.x