fix: updated sidebar positions in guides section

Co-authored-by: Kacper Żółkiewski <74975508+kacperzolkiewski@users.noreply.github.com>

Author: hejsztynx

docs/docs/guides/custom-context-menu.md

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 4
+sidebar_position: 3
 ---
 
 # Custom context menu

docs/docs/guides/emojis.mdx

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 3
+sidebar_position: 2
 ---
 
 import InteractiveExample from '@site/src/components/InteractiveExample';

docs/docs/guides/user-and-channel-mentions.mdx

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 2
+sidebar_position: 1
 ---
 
 import InteractiveExample from '@site/src/components/InteractiveExample';