Revise Lab 4 for canvas app creation and updates

Updated lab instructions for creating a canvas app, including new tasks for equipment checkout and modifications to the welcome screen.

Author: CeleneA

Instructions/Labs/LAB[PL-900]Lab4_Canvas_App.md

@@ -265,7 +265,7 @@ When a user selects a record in the Equipment list, we want to open the record i
     3.  **Minimum width:** 150
     4.  **Height:** 40
 
-1. Select the **SecondRecord1** container, Select the **Insert** button.
+1. Select the **SelectedRecord1** container, Select the **Insert** button.
 1. In the **Search** field, enter **Save**, and select the **Save** icon.
 1. Configure the **Save** button as follows:
 
@@ -344,3 +344,4 @@ Upon review, we have decided that we do not need to have the ability to create u
 
 
 
+