Render profile name when using Jinja2

[uilianries]

Parse the profile file name (including its extension) as profile_name for Jinja2 context.

Changelog: Feature: Render the profile file name as profile_name
Docs: conan-io/docs#3180

closes #13698

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[memsharded]

why not? I would expect the profile name to be PROFILE NAME: default

[uilianries]

sorry, I was not clear on this test. We are using a custom conf to store the profile_name, but the profile default is totally clear, so we store nothing.

I just updated it now to provide the default profile with the same content + os=Windows (because the 'build' profile must have a 'os' declared)

[AbrilRBS]

Conan profiles are not meant to have extensions afaik, but there sure is someone out there using them so +1 :)

Other than @memsharded's comments it lgtm