clightning-plugins: add prometheus patch for clightning 23.05

pkgs/clightning-plugins/default.nix

@@ -33,6 +33,14 @@ let
       patchRequirements =
         "--replace prometheus-client==0.6.0 prometheus-client==0.15.0"
         + " --replace pyln-client~=0.9.3 pyln-client~=23.02";
+      patches = [
+        # https://github.com/lightningd/plugins/pull/451
+        (pkgs.fetchpatch {
+          name = "202305-prometheus-msat-purge";
+          url = "https://github.com/lightningd/plugins/commit/f8a27b97a1b9ded8790c1f033b1f4268c0a6e210.patch";
+          sha256 = "sha256-0lFMhHHIi9bUU0+xaHhpnascNlFmr51JxE6e2F0s0zc=";
+        })
+      ];
     };
     rebalance = {
       description = "Keeps your channels balanced";
@@ -74,6 +82,8 @@ let
         patchShebangs '${script}'
       '';
 
+      patches = plugin.patches or [];
+
       passthru.path = "${drv}/${script}";
 
       meta = with lib; {