fix: bump nmrs to 3.5.3 to keep WireGuard preshared keys (#2212)

Fixes #2207.

Importing a WireGuard config with a preshared key through Settings didnt
work. nmrs wasnt setting `preshared-key-flags`. So NetworkManager
thought the key isnt required and therefore dropped it when it saved the
profile.

Fixed upstream in nmrs 3.5.3, so this just bumps the version
(freedesktop-rs/nmrs#551)



---

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Co-authored-by: clark-ja <37738506+theguy147@users.noreply.github.com>

cosmic-settings/Cargo.toml

@@ -55,7 +55,7 @@ locale1 = { git = "https://github.com/pop-os/dbus-settings-bindings", optional =
 sysinfo = { version = "=0.38.0", optional = true }
 mime-apps = { package = "cosmic-mime-apps", git = "https://github.com/pop-os/cosmic-mime-apps", features = ["tokio"], optional = true }
 notify = "8.2.0"
-nmrs = { version = "3.5.2", optional = true }
+nmrs = { version = "3.5.3", optional = true }
 regex = "1.13.1"
 ron = "0.12"
 rust-embed = "8.12.0"