Update Python version and remove funding sources in GitHub workflows

The python-package GitHub workflow has been updated to only support Python 3.x, as Python 2.x is no longer maintained. Additionally, PayPal and Patreon funding sources have been removed from the FUNDING.yml file.

Author: dvershinin

.github/FUNDING.yml

@@ -1,11 +1,8 @@
 community_bridge: null
-custom:
-- https://paypal.me/dvershinin
 github: dvershinin
 issuehunt: null
 ko_fi: null
 liberapay: null
 open_collective: null
 otechie: null
-patreon: getpagespeed
 tidelift: null

.github/workflows/pythonpackage.yml

@@ -9,7 +9,7 @@ jobs:
     strategy:
       max-parallel: 4
       matrix:
-        python-version: [ '2.x', '3.x' ]
+        python-version: [ '3.x' ]
 
     steps:
     - uses: actions/checkout@v1