prometheus-wireguard-exporter: 3.1.1 -> 3.2.0

https://github.com/MindFlavor/prometheus_wireguard_exporter/releases/tag/3.2.0

Previously, the exporter used `wg show all dump` by default to retrieve
information about wireguard peers. If a wireguard config is set, the interface is
now extracted automatically and the exporter runs `wg show <interface> dump`[1].

The cargo hash didn't change as no dependency updates were done in this
release.

[1] MindFlavor/prometheus_wireguard_exporter@4e332cb

pkgs/servers/monitoring/prometheus/wireguard-exporter.nix

@@ -2,13 +2,13 @@
 
 rustPlatform.buildRustPackage rec {
   pname = "wireguard-exporter";
-  version = "3.1.1";
+  version = "3.2.0";
 
   src = fetchFromGitHub {
     owner = "MindFlavor";
     repo = "prometheus_wireguard_exporter";
     rev = version;
-    sha256 = "1cc36bngpjq8138f98d2dl0imgisiph7xmw1i7csmjs03b4pnfcx";
+    sha256 = "0j6xcdbh6fl8z9zyl3rqnnxjkg30nigs9a6ndlbi2ycgmlnds55m";
   };
 
   cargoSha256 = "1ndb33bi08j40b4jkj4q7d3k0cw5fscz2gc2cc3134nbs2r7jamk";