Backport #20967
Currently, it's impossible to connect to self-signed TLS encrypted redis instances. The problem lies in inproper error handling, when building redis tls options - only invalid booleans are allowed to be used in `tlsConfig` builder. The problem is, when `strconv.ParseBool(...)` returns error, it always defaults to false - meaning it's impossible to set `tlsOptions.InsecureSkipVerify` to true.
Fixes #19213
Co-authored-by: Igor Rzegocki <ajgon@users.noreply.github.com>
Gitea was not able to supply any authentication parameters to it. So this brings support to do that, along with some light extraction of a couple of bits into some separate functions for easier testing.
I looked at other libraries supporting similar RedisUri-style connection strings (e.g. Lettuce), but it looks like this type of configuration is beyond what would typically be done in a connection string. Since gitea doesn't have configuration options for manually specifying all this redis connection detail, I went ahead and just chose straightforward names for these new parameters.
