Allow test.sh to be run from any dir

.github/workflows/ci.yaml

@@ -19,6 +19,5 @@ jobs:
       - name: Run test
         id: test
         run: |
-          cd ./test
           ./test.sh
 

test/test.sh

@@ -1,3 +1,4 @@
+cd "$(dirname "$0")"
 rm -f ./data.sqlite
 nix run -L --override-input process-compose-flake .. . -- -t=false
 [[ $(cat result.txt) == "Hello" ]] && echo "Test passed" || (echo "Test failed" && exit 1)