Adopt cap js postgres 1.3.1 (#254)

+ Adopt patch 1.3.1 for https://www.npmjs.com/package/@cap-js/postgres
+ Enable tests for this branch

Author: vmikhailenko

.github/workflows/maven.yml

@@ -5,9 +5,13 @@ name: Java CI with Maven
 
 on:
   push:
-    branches: [ main ]
+    branches:
+      - main
+      - postgres
   pull_request:
-    branches: [ main ]
+    branches: 
+      - main
+      - postgres
 
 jobs:
   build:

package.json

@@ -6,6 +6,6 @@
     "repository": "https://github.com/SAP-samples/cloud-cap-samples-java.git",
     "devDependencies": {
         "@sap/cds-dk": "^7.2",
-        "@cap-js/postgres": "~1.2"
+        "@cap-js/postgres": "~1.3"
     }
 }