Print values of env vars if they are invalid

[DL6ER]

What does this implement/fix?

Print values of env vars if invalid, example:

ENV FTLCONF_dns_listeningMode = "not_existing"

leads to

2025-02-24 19:08:11.074 CET [2045070M] WARNING: ENV FTLCONF_dns_listeningMode = "not_existing" is not an allowed option, allowed options are: ["LOCAL","SINGLE","BIND","ALL","NONE"]

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Related issue or feature (if applicable): Fixes #2262

Pull request in docs with documentation (if applicable): N/A

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[PromoFaux]

Looks to work as advertised. Is it intended that both the WARNING and the ERROR are printed?

[yubiuser]

Works perfectly. But see Adams comment.

[DL6ER]

See my last commit :-)

[yubiuser]

[yubiuser]

[PromoFaux]

Ah - was just coming back to approve this, @yubiuser beat me to it :)