refactor: Now new feed selection test suite is independent
refactor: Now new feed selection test suite is independent

New feed selection was using the data in oldFeed variable which was returning from
the loadFeed callback in initial entries test suite. Now I have called the loadFeed twice
to make sure that the oldFeed variable data should be separated from other tests for
consistency.

rehanumar/p6-feed-reader-testing,rehanumar/p6-feed-reader-testing