gh-102498 Clean up unused variables and imports in the email module (#102482)

gh-102498 Clean up unused variables and imports in the email module  (#102482)

* Clean up unused variables and imports in the email module

* Remove extra newline char

* Remove superflous dict+unpacking syntax

* Remove unused 'msg' var

* Clean up unused variables and imports in the email module

* Remove extra newline char

* Remove superflous dict+unpacking syntax

* Remove unused 'msg' var

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Co-authored-by: Barry Warsaw <barry@python.org>