chore(mix): use MixRlnSpamProtection.new constructor, bump plugin pin

Rename the call site to the typedesc constructor
MixRlnSpamProtection.new (was newMixRlnSpamProtection) to match
nim-libp2p conventions, and bump the mix-rln-spam-protection-plugin
pin to 61ee3e5 which provides the renamed constructor.

Author: chaitanyaprem

logos_delivery.nimble

@@ -62,7 +62,7 @@ requires "nim >= 2.2.4",
 # Packages not on nimble (use git URLs)
 
 requires "https://github.com/logos-messaging/nim-ffi#v0.1.3"
-requires "https://github.com/logos-co/mix-rln-spam-protection-plugin.git#23b278b4ab21193ad4e9ce76015f008db7332a6f"
+requires "https://github.com/logos-co/mix-rln-spam-protection-plugin.git#61ee3e5aacb6b224b70e164ef7d0a5714fe66b26"
 
 # nim-libp2p-mix: extracted mix protocol used by the plugin and by waku's
 # mix integration layer. Tip of experiment/drop-nimble-lock (PR #14, stacked

logos_delivery/waku/waku_mix/protocol.nim

@@ -113,7 +113,7 @@ proc new*(
     spamProtectionConfig.userMessageLimit = userMessageLimit.get()
   # rlnResourcesPath left empty to use bundled resources (via "tree_height_/" placeholder)
 
-  let spamProtection = newMixRlnSpamProtection(spamProtectionConfig).valueOr:
+  let spamProtection = MixRlnSpamProtection.new(spamProtectionConfig).valueOr:
     return err("failed to create spam protection: " & error)
 
   var m = WakuMix(