Expose mtls certificate config params in python and php configuration templates

[eddiesholl]

These changes allow the generated client for php and python to support endpoints configured with mTLS. It means users can get a successful request to go through without needing to make any edits to the generated code in these 2 languages.

This fixes the previously raised issue #12776 in a limited way, for just these languages. The same change could be made to all the other generators, I'm just making the enhancements I need for now.

PHP: @jebentier @dkarlovi @mandrean @jfastnacht @ybelenko @renepardon
Python: @cbornet @tomplus @krjakbrjak @fa0311 @multani

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[wing328]

thanks for the PR

did you test this fix locally to confirm it works for your use cases?

[eddiesholl]

thanks for the PR

did you test this fix locally to confirm it works for your use cases?

Yes, I built the generator locally and ran a generation using the built jar. I was able to get the generated client for php and python to make an mtls request out of the box

[wing328]

thanks for the details

PR merged.

thanks for the contribution.