chore(deps): update postgres docker digest to b3ef52d (#2838)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| postgres | service | digest | `1ffc019` -> `b3ef52d` |

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.github/workflows/ci.yml

@@ -53,7 +53,7 @@ jobs:
 
     services:
       postgres:
-        image: postgres@sha256:1ffc019dae94eca6b09a49ca67d37398951346de3c3d0cfe23d8d4ca33da83fb
+        image: postgres@sha256:b3ef52d269e0050ac3ba8266d8bc9650987412f60d66472fdf7e14f523ecc506
         env:
           POSTGRES_PASSWORD: postgres
           POSTGRES_DB: jabref

.github/workflows/copilot-setup-steps.yml

@@ -19,7 +19,7 @@ jobs:
 
     services:
       postgres:
-        image: postgres@sha256:1ffc019dae94eca6b09a49ca67d37398951346de3c3d0cfe23d8d4ca33da83fb
+        image: postgres@sha256:b3ef52d269e0050ac3ba8266d8bc9650987412f60d66472fdf7e14f523ecc506
         env:
           POSTGRES_PASSWORD: postgres
           POSTGRES_DB: jabref