os-freeradius: EAP max TLS version increase

[Soswald]

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Describe the solution you'd like Currently the TLS version is hardcoded to a maximum of 1.2 via the entry tls_max_version = "1.2" in the config file /usr/local/etc/raddb/mods-enabled/eap generated by /usr/local/opnsense/service/templates/OPNsense/Freeradius/mods-enabled-eap

Since both OpenSSL (since 1.1.1) and FreeRADIUS (since 3.0.26) support TLS 1.3, the maximum version should probably be increased to this version if nothing else speaks against it.

Describe alternatives you've considered None