fix(tests): fix flaky time-based tests (#699)

* fix(tests): fix flaky time-based tests

* test: replace time package with a mock
Using a dedicated dependency would have been awesome, but i try to keep this repo with minimal dependencies

.github/workflows/test.yml

@@ -10,6 +10,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     strategy:
+      fail-fast: false
       matrix:
         go:
           - "1.18"
@@ -19,6 +20,7 @@ jobs:
           - "1.22"
           - "1.23"
           - "1.24"
+          - "1.25"
           - "1.x"
     steps:
       - uses: actions/checkout@v5