Add references to FreeCam camera tilting keybinds (#1235)

## Changes

- Added respective references to the key binds for the camera tilting
feature, which can be accessed by the `Z` and `C` keys while actively
inside of freecam.

## Checks

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- [X] This contribution was created in whole or in part by me, and I
have the right to submit it under the terms of this repository's open
source licenses.
- [X] I understand and agree that this contribution and a record of it
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- [x] To the best of my knowledge, all proposed changes are accurate.

---------

Co-authored-by: IgnisRBX <[email protected]>

Author: metaclasscat

content/en-us/production/publishing/thumbnails.md

@@ -204,6 +204,10 @@ Once in free camera mode, you can use the following controls:
     <td><kbd>Q</kbd> <kbd>E</kbd></td>
     <td>Moves the camera down/up.</td>
   </tr>
+  <tr>
+    <td><kbd>Z</kbd> <kbd>C</kbd></td>
+    <td>Tilts the camera left/right (roll).</td>
+  </tr>
   <tr>
     <td><kbd>Shift</kbd></td>
     <td>In combination with any movement key, changes the camera speed.</td>