DEV | Bugfix for post list, follow and tags

[x] The Post List view should be updated to get the posts of the followed users. Currently it is commented.
[x] In the friends page when the Follow button is clicked the user should be followed and the link should change to unfollow.
[x] The tags should be displayed in the post list page. It may have been removed after the bookmarking developments.
[ ] The project name should be SWE574 on the base.html file.

swe574-spring23 / SWE574