Fix no-misused-promises in SpamCheckEndpointPluginManager

Draupnir\apps\draupnir\src\webapis\SynapseHTTPAntispam\SpamCheckEndpointPluginManager.ts
  43:36  error  Promise returned in function argument where a void return was expected  @typescript-eslint/no-misused-promises

Trying to fix this naively will lead to a cascade of issues but this is ultimately a fix via splitting into blocking and non blocking.

Author: FSG-Cat

apps/draupnir/src/protections/BlockInvitationsOnServerProtection.tsx

@@ -112,7 +112,7 @@ export class SynapseHTTPUserMayInvite {
   }
 
   unregisterListeners(): void {
-    this.synapseHTTPAntispam.userMayInviteHandles.unregisterHandle(
+    this.synapseHTTPAntispam.userMayInviteHandles.unregisterBlockingHandle(
       this.synapseHTTPCallback
     );
   }

apps/draupnir/src/protections/RoomTakedown/SynapseHTTPAntispamRoomExplorer.ts

@@ -88,13 +88,13 @@ export class SynapseHTTPAntispamRoomExplorer implements RoomExplorer {
   }.bind(this);
 
   unregisterListeners(): void {
-    this.synapseHTTPAntispam.checkEventForSpamHandles.unregisterHandle(
+    this.synapseHTTPAntispam.checkEventForSpamHandles.unregisterNonBlockingHandle(
       this.handleCheckEventForSpam
     );
-    this.synapseHTTPAntispam.userMayInviteHandles.unregisterHandle(
+    this.synapseHTTPAntispam.userMayInviteHandles.unregisterNonBlockingHandle(
       this.handleUserMayInvite
     );
-    this.synapseHTTPAntispam.userMayJoinRoomHandles.unregisterHandle(
+    this.synapseHTTPAntispam.userMayJoinRoomHandles.unregisterNonBlockingHandle(
       this.handleUserMayJoin
     );
     this.batcher.dispose();

apps/draupnir/src/webapis/SynapseHTTPAntispam/SpamCheckEndpointPluginManager.ts

@@ -36,10 +36,13 @@ export class SpamCheckEndpointPluginManager<CBArguments extends unknown[]> {
     this.nonBlockingHandles.add(handle);
   }
 
-  public unregisterHandle(
-    handle: BlockingCallback<CBArguments> | NonBlockingCallback<CBArguments>
+  public unregisterBlockingHandle(handle: BlockingCallback<CBArguments>): void {
+    this.blockingHandles.delete(handle);
+  }
+
+  public unregisterNonBlockingHandle(
+    handle: NonBlockingCallback<CBArguments>
   ): void {
-    this.blockingHandles.delete(handle as BlockingCallback<CBArguments>);
     this.nonBlockingHandles.delete(handle);
   }