[Bug] Duplicate posts with a combination of same feed id and post id are not removed.

[KristofferStrube]

Describe the bug
The mechanism that removes duplicate content from multiple RSS feeds doesn't seem to work. Some of my blog posts appear in both my general feed and my dotnet feed but have the same id in both feeds so the duplicate should be removed.
I note this at the end of this PR: #132

To Reproduce
Steps to reproduce the behavior:

1. Go to https://www.wearedotnet.io/KristofferStrube
2. Observe duplicate content.

Or do the following to reproduce in the search results for content:

1. Go to https://www.wearedotnet.io/content/blazor
2. Observe that my posts appear twice on the page.

Expected behavior
I expected posts from feeds with a combination of the same feed id and post ids to have duplicate entries removed.

Screenshots

Desktop (please complete the following information):

• OS: Windows 10
• Browser Chrome
• Version 112.0.5615.139

Additional context
If this isn't going to be fixed then I would just like to have my personal feed changed to https://kristoffer-strube.dk/RSS.personal.xml which doesn't have any overlap with my dotnet feed.

Also, your project rules! ❤

[DeeJayTC]

Hey we're working on this, might take some time tho. Keeping you updated