[Context] Adds react_quietly method to context (#2834)

* [Context] Adds react_quietly method to context

This allows developers to emojis to command messages
This is a modified version of tick()

It accepts True/False for Tick/Cross emoji and in addition to that any other emoji the bot can see

* Removed True/False support from react quietly

* Stopped catching InvalidArgument on react_quietly so that is propagated to devs

redbot/core/commands/context.py

@@ -1,6 +1,6 @@
 import asyncio
 import contextlib
-from typing import Iterable, List
+from typing import Iterable, List, Union
 import discord
 from discord.ext import commands
 
@@ -86,6 +86,22 @@ class Context(commands.Context):
         else:
             return True
 
+    async def react_quietly(
+        self, reaction: Union[discord.Emoji, discord.Reaction, discord.PartialEmoji, str]
+    ) -> bool:
+        """Adds a reaction to to the command message.
+        Returns
+        -------
+        bool
+            :code:`True` if adding the reaction succeeded.
+        """
+        try:
+            await self.message.add_reaction(reaction)
+        except discord.HTTPException:
+            return False
+        else:
+            return True
+
     async def send_interactive(
         self, messages: Iterable[str], box_lang: str = None, timeout: int = 15
     ) -> List[discord.Message]: