ansible: Simplify stage2 postgres install/setup

Don't need sudo -u postgres just to get the paths and no need to source
nix-daemon.sh explicitly.

Author: mmlb

ansible/tasks/stage2-setup-postgres.yml

@@ -62,20 +62,14 @@
   when: stage2
   become: true
   block:
-    - name: Resolve postgres env store path
+    - name: Resolve postgres env from nix binary cache
       ansible.builtin.shell: |
-        sudo -u postgres bash -c "
-          . /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh &&
-          nix build --no-link --print-out-paths github:supabase/postgres/{{ git_commit_sha }}#postgres-env-{{ postgresql_major_version }}
-        "
+        nix build --no-link --print-out-paths github:supabase/postgres/{{ git_commit_sha }}#postgres-env-{{ postgresql_major_version }}
       register: postgres_env_path
 
     - name: Install postgres env from nix binary cache
       ansible.builtin.shell: |
-        sudo -u postgres bash -c "
-          . /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh &&
-          nix-env --set {{ postgres_env_path.stdout }}
-        "
+        sudo -u postgres bash -c 'nix-env --set {{ postgres_env_path.stdout }}'
 
     - name: Set ownership and permissions for file and dirs
       ansible.builtin.file: