Faster $simplePie->get_items() (#4263)
Faster $simplePie->get_items() (#4263)

Implement one of the TODOs from https://github.com/FreshRSS/FreshRSS/pull/4220 :
use `$simplePie->get_items()` instead of very slow `$simplePie->get_item($i)`
aledeg/FreshRSS,aledeg/FreshRSS,FreshRSS/FreshRSS,FreshRSS/FreshRSS,aledeg/FreshRSS,FreshRSS/FreshRSS,Alkarex/FreshRSS,FreshRSS/FreshRSS,Alkarex/FreshRSS,Alkarex/FreshRSS,aledeg/FreshRSS,Alkarex/FreshRSS