remove the concurrency block from the reused test workflow

Author: ThoSap

.github/workflows/test.yml

@@ -3,10 +3,6 @@ name: Tests
 on:
   workflow_call:
 
-concurrency:
-  group: ${{ github.ref }}
-  cancel-in-progress: true
-
 jobs:
   test:
     name: Tests (PostgreSQL ${{ matrix.postgres-version }})