Migrate /unmod command to Helix API (#4001)

Co-authored-by: Felanbird <41973452+Felanbird@users.noreply.github.com>
Co-authored-by: pajlada <rasmus.karlsson@pajlada.com>

src/providers/twitch/api/Helix.hpp

@@ -352,6 +352,17 @@ enum class HelixAddChannelModeratorError {
     Forwarded,
 };
 
+enum class HelixRemoveChannelModeratorError {
+    Unknown,
+    UserMissingScope,
+    UserNotAuthorized,
+    TargetNotModded,
+    Ratelimited,
+
+    // The error message is forwarded directly from the Twitch API
+    Forwarded,
+};
+
 class IHelix
 {
 public:
@@ -494,6 +505,12 @@ public:
         FailureCallback<HelixAddChannelModeratorError, QString>
             failureCallback) = 0;
 
+    // https://dev.twitch.tv/docs/api/reference#remove-channel-moderator
+    virtual void removeChannelModerator(
+        QString broadcasterID, QString userID, ResultCallback<> successCallback,
+        FailureCallback<HelixRemoveChannelModeratorError, QString>
+            failureCallback) = 0;
+
     virtual void update(QString clientId, QString oauthToken) = 0;
 };
 
@@ -629,6 +646,12 @@ public:
         FailureCallback<HelixAddChannelModeratorError, QString> failureCallback)
         final;
 
+    // https://dev.twitch.tv/docs/api/reference#remove-channel-moderator
+    void removeChannelModerator(
+        QString broadcasterID, QString userID, ResultCallback<> successCallback,
+        FailureCallback<HelixRemoveChannelModeratorError, QString>
+            failureCallback) final;
+
     void update(QString clientId, QString oauthToken) final;
 
     static void initialize();