flake: Bump erpnext input flake to fix systemd

dependencies

• Updated input 'erpnext':
    'git+https://git.pub.solar/axeman/erpnext-nix?ref=main&rev=28a47059b7b723f2709a4f81384015ae4e8f8562' (2023-07-17)
  → 'git+https://git.pub.solar/axeman/erpnext-nix?ref=main&rev=44a0598bd1e7533033cd9d1170de7d83dff80a2f' (2023-07-17)
• Updated input 'erpnext/devshell':
    'github:numtide/devshell/6b2554d28d46bfa6e24b941e999a145760dad0e1' (2023-06-05)
  → 'github:numtide/devshell/f9238ec3d75cefbb2b42a44948c4e8fb1ae9a205' (2023-07-03)
• Updated input 'erpnext/nixpkgs':
    'github:NixOS/nixpkgs/6cee3b5893090b0f5f0a06b4cf42ca4e60e5d222' (2023-07-16)
  → 'github:NixOS/nixpkgs/6cee3b5893090b0f5f0a06b4cf42ca4e60e5d222' (2023-07-16)

flake.lock

@@ -101,11 +101,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1685972731,
-        "narHash": "sha256-VpwVUthxs3AFgvWxGTHu+KVDnS/zT3xkCtmjX2PjNQs=",
+        "lastModified": 1688380630,
+        "narHash": "sha256-8ilApWVb1mAi4439zS3iFeIT0ODlbrifm/fegWwgHjA=",
         "owner": "numtide",
         "repo": "devshell",
-        "rev": "6b2554d28d46bfa6e24b941e999a145760dad0e1",
+        "rev": "f9238ec3d75cefbb2b42a44948c4e8fb1ae9a205",
         "type": "github"
       },
       "original": {
@@ -164,11 +164,11 @@
         "systems": "systems"
       },
       "locked": {
-        "lastModified": 1689622186,
-        "narHash": "sha256-6GaWBmm3B4bSNlO5h2q7C3YfXfMp8wgowClAg79JfYc=",
+        "lastModified": 1689637049,
+        "narHash": "sha256-mSfmuSRLmztRjo030Z4y1QQCjuMczyKC+eVmVdb+nQI=",
         "ref": "main",
-        "rev": "28a47059b7b723f2709a4f81384015ae4e8f8562",
-        "revCount": 28,
+        "rev": "44a0598bd1e7533033cd9d1170de7d83dff80a2f",
+        "revCount": 30,
         "type": "git",
         "url": "https://git.pub.solar/axeman/erpnext-nix"
       },