update Open Source Docs from Roblox internal teams

Author: rbx-open-source-docs[bot]

content/common/navigation/documentation.yaml

@@ -67,3 +67,12 @@ columns:
           navigation: /education.yaml
           path:  /education/educator-onboarding/landing
       # EDUCATION NAV REWORK
+
+    # COURSES NAV REWORK
+    - title: Courses
+      path: /courses
+      items:
+        - title: All Courses
+          navigation: /courses/courses.yaml
+          path: /courses
+      # COURSES NAV REWORK

content/en-us/tutorials/curriculums/environmental-art/develop-polished-assets.md

@@ -89,7 +89,7 @@ The previous point is near impossible to remove entirely, but you can set Studio
 
 ### Trim sheets
 
-**Trim sheets** are textures that tile both on either the X **or** Y axis, and they allow you to add significantly more visual complexity to your experiences without having to import additional textures, saving you a negative impact on memory. Each row or column of a trim sheet has a unique visual appearance, giving you many different surface treatments to choose from when you're mapping UV data to a mesh. For example, the door frame and ceiling assets in the following two images use different layers of the same trim sheet to add detail work to the space.
+**Trim sheets** are textures that tile on either the X **or** Y axis, and they allow you to add significantly more visual complexity to your experiences without having to import additional textures, saving you a negative impact on memory. Each row or column of a trim sheet has a unique visual appearance, giving you many different surface treatments to choose from when you're mapping UV data to a mesh. For example, the door frame and ceiling assets in the following two images use different layers of the same trim sheet to add detail work to the space.
 
 <GridContainer numColumns="2">
   <figure>