Check mark reactions in welcome channel approve user.

A check mark reaction emoji can be used to approve a user, if it is done in the Join/Leave message channel.
It requires the one reacting to have the "Manage Roles" permission.

commands/gatekeep.py

@@ -207,6 +207,30 @@ class Gatekeep(Extension):
             str(gk.gatekeep_approve_message).format(member=user, guild=ctx.guild)
         )
 
+    @listen(events.MessageReactionAdd)
+    async def on_reaction_add(self, reaction: events.MessageReactionAdd):
+        if not reaction.emoji.name in [
+            "✅",
+            "☑",
+            "✔",
+        ] or not reaction.author.has_permission(Permissions.MANAGE_ROLES):
+            return
+
+        gk: GatekeepModel
+        gk, _ = GatekeepModel.get_or_create(guild_id=reaction.guild.id)
+        jl: JoinLeaveModel
+        jl, _ = JoinLeaveModel.get_or_create(guild_id=reaction.guild.id)
+
+        if reaction.message.channel.id != jl.message_channel:
+            return
+
+        await reaction.message.author.add_role(int(gk.gatekeep_approve_role))
+        await reaction.message.channel.send(
+            str(gk.gatekeep_approve_message).format(
+                member=reaction.message.author, guild=reaction.guild
+            )
+        )
+
     @slash_command(
         name="captcha",
         description="Complete a captcha",