Fix "method_lines" issue in src/elivepatch_server/resources/dispatcher.py

[aliceinwire]

Function post has 26 lines of code (exceeds 25 allowed). Consider refactoring.

https://codeclimate.com/github/gentoo/elivepatch-server/src/elivepatch_server/resources/dispatcher.py#issue_5d277a45d24643000100001b