test: Turn util/test_runner into functional test

The moved portion can be reviewed via:

--color-moved=dimmed-zebra  --color-moved-ws=ignore-all-space

.github/workflows/ci.yml

@@ -390,9 +390,6 @@ jobs:
           (Get-Content "test/config.ini") -replace '(?<=^SRCDIR=).*', '${{ github.workspace }}' -replace '(?<=^BUILDDIR=).*', '${{ github.workspace }}' -replace '(?<=^RPCAUTH=).*', '${{ github.workspace }}/share/rpcauth/rpcauth.py' | Set-Content "test/config.ini"
           Get-Content "test/config.ini"
 
-      - name: Run util tests
-        run: py -3 test/util/test_runner.py
-
       - name: Run rpcauth test
         run: py -3 test/util/rpcauth-test.py