feat(frontend): add discord link (#2343)

# Description

Please include a summary of the changes and the related issue. Please
also include relevant motivation and context.

## Checklist before requesting a review

Please delete options that are not relevant.

- [ ] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my code
- [ ] I have commented hard-to-understand areas
- [ ] I have ideally added tests that prove my fix is effective or that
my feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged

## Screenshots (if appropriate):

frontend/lib/components/Menu/components/SocialsButtons/SocialsButtons.tsx

@@ -30,6 +30,13 @@ export const SocialsButtons = (): JSX.Element => {
         handleHover={true}
         onClick={() => handleClick("https://twitter.com/quivr_brain")}
       />
+      <Icon
+        name="discord"
+        color="black"
+        size="small"
+        handleHover={true}
+        onClick={() => handleClick("https://discord.gg/HUpRgp2HG8")}
+      />
     </div>
   );
 };

frontend/lib/helpers/iconList.ts

@@ -9,6 +9,7 @@ import { CiFlag1 } from "react-icons/ci";
 import {
   FaCheck,
   FaCheckCircle,
+  FaDiscord,
   FaFileAlt,
   FaGithub,
   FaKey,
@@ -78,6 +79,7 @@ export const iconList: { [name: string]: IconType } = {
   copy: LuCopy,
   custom: MdDashboardCustomize,
   delete: MdDeleteOutline,
+  discord: FaDiscord,
   download: IoCloudDownloadOutline,
   edit: MdOutlineModeEditOutline,
   email: MdAlternateEmail,