net/traefik: Update to upstream release 3.7.6

Details:

• Bug- and docfixes, see https://github.com/traefik/traefik/releases/tag/v3.7.6
• Fixes multiple vulnerabilities in the process, see CVE IDs and release notes linked above.

MFH: 2026Q2
Security: CVE-2026-54763

		CVE-2026-54764
		CVE-2026-54765