ci: limit test workers and remove db:ensure dependency (#490)

# Limit test workers and remove unnecessary dependency

This PR makes two changes to improve test reliability and build efficiency:

1. Added `--maxWorkers=1` flag to vitest commands in the client package to prevent test flakiness by running tests sequentially
2. Removed the `db:ensure` dependency from the `test:unit` command in the edge-worker package since unit tests don't require a database connection

These changes should help reduce test flakiness and improve build times by removing unnecessary dependencies.

Author: jumski

pkgs/client/project.json

@@ -149,7 +149,7 @@
         "commands": [
           "../../scripts/supabase-start-locked.sh .",
           "psql 'postgresql://postgres:postgres@localhost:50522/postgres' -c 'SELECT pgflow_tests.reset_db()'",
-          "vitest run __tests__/integration/"
+          "vitest run __tests__/integration/ --poolOptions.threads.singleThread"
         ],
         "parallel": false
       }
@@ -174,7 +174,7 @@
         "commands": [
           "../../scripts/supabase-start-locked.sh .",
           "psql 'postgresql://postgres:postgres@localhost:50522/postgres' -c 'SELECT pgflow_tests.reset_db()'",
-          "vitest run __tests__/"
+          "vitest run __tests__/ --poolOptions.threads.singleThread"
         ],
         "parallel": false
       }

pkgs/edge-worker/project.json

@@ -135,7 +135,7 @@
       }
     },
     "test:unit": {
-      "dependsOn": ["db:ensure", "^build"],
+      "dependsOn": ["^build"],
       "executor": "nx:run-commands",
       "local": true,
       "inputs": ["default", "^production"],