docker (e2e): use shared volume for SàT's local dir:

It is necessary to have a shared local dir to let libervia access files.

docker/docker-compose_e2e.yml

@@ -43,6 +43,8 @@ services:
     environment:
       SAT_TEST_ENV_E2E: "1"
       SAT_TEST_ENV_E2E_LIBERVIA: "1"
+    volumes:
+      - sat_data:/home/sat/.local/share/sat
     ports:
       # VNC server for Libervia e2e tests visual mode
       - 5900
@@ -58,6 +60,8 @@ services:
       - sat
     environment:
       LIBERVIA_PASSPHRASE: test_e2e
+    volumes:
+      - sat_data:/home/sat/.local/share/sat
     ports:
         - "8080"
         - "8443"
@@ -65,3 +69,6 @@ services:
       default:
         aliases:
           - libervia.test
+
+volumes:
+  sat_data: