Update LineJoinMode.yaml (#1074)

Added figures from the UIStroke class page, as images are referenced in
the table although none exist Changed reference to the "Applying Strokes
Article" to reference the UIStroke class page (said article does not
exist).

This documentation error was brought to my attention by
[@xaxa](https://devforum.roblox.com/u/xaxa) in [this devforum
post](https://devforum.roblox.com/t/enumlinejoinmode-documentation-appears-to-be-outdated/3603081).

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---------

Author: sammygrey

content/en-us/reference/engine/enums/LineJoinMode.yaml

@@ -7,29 +7,32 @@ description: |
   This enum is used by `Class.UIStroke.LineJoinMode` to determine how corners
   are interpreted.
 
-  See also:
-
-  For a more detailed walkthrough of the UIStroke object, take a look at the
-  Applying Strokes article.
+  For a more detailed walkthrough of the `Class.UIStroke` object, see [here](../../../ui/appearance-modifiers.md#stroke).
 code_samples:
 tags: []
 deprecation_message: ''
 items:
   - name: Round
     summary: |
-      The corners are rounded (see image above).
+      The corners are rounded.
+
+      <img src="/assets/ui/ui-objects/UIStroke-LineJoinMode-Round.png" width="376" />
     value: 0
     tags: []
     deprecation_message: ''
   - name: Bevel
     summary: |
-      The corners are beveled (see image above).
+      The corners are beveled.
+
+      <img src="/assets/ui/ui-objects/UIStroke-LineJoinMode-Bevel.png" width="376" />
     value: 1
     tags: []
     deprecation_message: ''
   - name: Miter
     summary: |
-      The corners are mitered (see image above).
+      The corners are mitered.
+
+      <img src="/assets/ui/ui-objects/UIStroke-LineJoinMode-Miter.png" width="376" />
     value: 2
     tags: []
     deprecation_message: ''