Personal Library - Functional tests blocking FCC tests?

Step1
I set the NODE_ENV and DB(MongoDB) key in the replit’s secrets tab.

Step2
I implemented the routing process in the file routes/api.js.

Step3
I ran FCC tests and passed except for the last FCC8 (All 10 functional tests required are complete and passing).

Step4
I implemented functional tests in tests/2_functional-tests.js.

Step5
I started the app by pressing the run button in the replit

Step6
I ran a functional test on the replit console and saw 10 passing messages

Step7
Now when I ran the FCC tests and checked the results, all but the first FCC1 failed (Test timed out).

As far as the behavior of the app is concerned, the code written in the functional test seems to block the FCC test. Could you point out if there are any suspicious parts in my code?

My project links
Replit: https://boilerplate-project-library.makotoaraki.repl.co
Github: GitHub - Makoto-Araki/boilerplate-project-library: A boilerplate for a freeCodeCamp project.

solution: boilerplate-project-library - Replit

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Challenge: Quality Assurance Projects - Personal Library

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