[IMP] web: add TikTok icon

This commit patches the font awesome library to add an icon for the
TikTok social network. Users are now able to add these icons with the
media dialog. Now, the TikTok icon works like all other font awesome
icons, with the new class introduced by this commit: `fa-tiktok`.

Technical note:
In order to add this new icon, a new font that contains only the TikTok
logo has been created.

task-3235451

closes odoo/odoo#116383

Signed-off-by: Vray Benjamin (bvr) <bvr@odoo.com>

addons/web/static/src/scss/fontawesome_overridden.scss

+// This is a patch of the font awesome library to add the TikTok icon.
+@font-face {
+    font-family: 'FontAwesome-tiktok-only';
+    src: url('../../src/fonts/tiktok_only.woff');
+    font-weight: normal;
+    font-style: normal;
+    font-display: block;
+}
+.fa.fa-tiktok {
+    font-family: 'FontAwesome-tiktok-only' !important;
+
+    &:before {
+        content: '\e07b';
+    }
+}
+
 // This is rtl language specific fix
 // It will override the font awesome symbols and flip them 180 degree
 .o_rtl {