Rename python Driver method 'Postprocessing' to 'Finalize'

[kursatyurt]

Proposed Changes

The driver method Postprocessing() actually frees all the containers and finalizes the driver. As it does not reflect what is actually done and is easy to confuse with the method Postprocess(), the PR proposes renaming the method to Finalize().

PR Checklist

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• My contribution generates no new compiler warnings (try with --warnlevel=3 when using meson).
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• I have added a test case that demonstrates my contribution, if necessary.
• I have updated appropriate documentation (Tutorials, Docs Page, config_template.cpp), if necessary.

[pcarruscag]

LGTM 👍