test: Update process-compose-flake

Also wrap in startScript because 'command' no longer does that.

nix/postgres.nix

@@ -258,19 +258,26 @@ in
           '';
 
         # DB process
-        ${cfg.name} = {
-          command = ''
-            set -x
-            export PATH="${postgresPkg}"/bin:$PATH
-            export LOCKDIR="/tmp"
-            postgres -k $LOCKDIR -D ${cfg.dataDir}
-          '';
-          depends_on."${cfg.name}-init".condition = "process_completed_successfully";
-          # SIGINT (= 2) for faster shutdown: https://www.postgresql.org/docs/current/server-shutdown.html
-          shutdown.signal = 2;
-          # https://github.com/F1bonacc1/process-compose#-auto-restart-if-not-healthy
-          availability.restart = "on_failure";
-        };
+        ${cfg.name} =
+          let
+            startScript = pkgs.writeShellApplication {
+              name = "start-postgres";
+              text = ''
+                set -x
+                export PATH="${postgresPkg}"/bin:$PATH
+                export LOCKDIR="/tmp"
+                postgres -k "$LOCKDIR" -D ${cfg.dataDir}
+              '';
+            };
+          in
+          {
+            command = startScript;
+            depends_on."${cfg.name}-init".condition = "process_completed_successfully";
+            # SIGINT (= 2) for faster shutdown: https://www.postgresql.org/docs/current/server-shutdown.html
+            shutdown.signal = 2;
+            # https://github.com/F1bonacc1/process-compose#-auto-restart-if-not-healthy
+            availability.restart = "on_failure";
+          };
       };
   };
 }

test/flake.lock

@@ -54,11 +54,11 @@
     },
     "process-compose-flake": {
       "locked": {
-        "lastModified": 1687211949,
-        "narHash": "sha256-PKZhjtrLkN1+AuWiv+m+n0tL5xcrjwXRdAR6pS+UwxI=",
+        "lastModified": 1687298948,
+        "narHash": "sha256-7Lu4/odCkkwrzR8Mo+3D+URv4oLap8WWLESzi/75eb0=",
         "owner": "Platonic-Systems",
         "repo": "process-compose-flake",
-        "rev": "1483bd7fecd59254d8531b6c3202f3f765b22468",
+        "rev": "5bdb90b85642901cf9a5dccfe8c907091c261604",
         "type": "github"
       },
       "original": {