Module data lives in /var/lib, now that nothing is mid-cutover

The /services paths were the adopted-node pattern doing its job: take
replaced containers over the predecessor's data without moving a byte
(gitea set it — 'its data never moved'). With every cutover done the
exception has no reason left, and the operator called it: a nox
module's world is /var/lib/<module>, data included. Six modules
repathed; mssql keeps its /services path deliberately — it is still
held, HAL-run, and moves at its own take. Both trees are one
filesystem, so each move is a rename.

modules/mongodb/module.json

@@ -64,7 +64,7 @@
     {
       "id": "data",
       "type": "directory",
-      "path": "/services/mongodb/db-data",
+      "path": "/var/lib/mongodb/data",
       "mode": "0700"
     },
     {
@@ -86,7 +86,7 @@
         "27017"
       ],
       "volumes": [
-        "/services/mongodb/db-data:/data/db",
+        "/var/lib/mongodb/data:/data/db",
         "/var/lib/mongodb/root.secret:/run/secrets/root:ro"
       ]
     },