[release/4][BACKPORT] fix: Bump Traefik Forward Auth image tag

[d2iq-mergebot]

This is a backport of the following PR:

#1344

What type of PR is this?

Fix

What this PR does/ why we need it:

This bumps Traefik Forward Auth to pull in a fix. See mesosphere/traefik-forward-auth#49.

Which issue(s) this PR fixes:

https://jira.d2iq.com/browse/D2IQ-80372

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[traefik-forward-auth] Upgrade container image to 3.0.3, pulling in a fix for URL pattern matching.

Checklist

• The commit message explains the changes and why are needed.
• The code builds and passes lint/style checks locally.
• The relevant subset of integration tests pass locally.
• The core changes are covered by tests.
• The documentation is updated where needed.

[d2iq-mergebot]

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