Validate files specified via `-tlsKeyFile` and `-tlsCertFile` cmd-line flags on the process start-up. Previously, validation happened on the first connection accepted by HTTP server.
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6608
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Co-authored-by: hagen1778 <roman@victoriametrics.com>
* lib/{httpserver,netutil}: allow to define min and max TLS version of the http server
* lib/httpserver: added descriptions about tls supported versions
* lib/netutil: check minimal tls version, added supported tls versions to error
* wip
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
