Allow passing ssl_ca_data argument to SSLConnection

[m-novikov]

Is your feature request related to a problem?

Currently it's only possible to pass CA chain to SSLConnection if named file exists in the filesystem. In some use-cases certificates could be stored in-memory.

Describe the solution you'd like

I suppose ssl_ca_data argument would conform to the current API

Describe alternatives you've considered

Custom connection class, but it's also problematic as described in #1209

Additional context

No response

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