shared/generator: Ensure growfs unit runs after repart

When deploying an image using systemd-repart and systemd-growfs one
should have the image expanded entirely and ready to use after the first
boot. This ensures that growfs does not occur before repart, thus
requiring a second boot.

src/shared/generator.c

@@ -537,7 +537,7 @@ int generator_hook_up_growfs(
                 "DefaultDependencies=no\n"
                 "BindsTo=%%i.mount\n"
                 "Conflicts=shutdown.target\n"
-                "After=%%i.mount\n"
+                "After=systemd-repart.service %%i.mount\n"
                 "Before=shutdown.target%s%s\n",
                 program_invocation_short_name,
                 target ? " " : "",