Ternary conditional operators (#952)

## Changes

Minor change which converts some variable setting into ternary
operations to help simplify the code.

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---------

Author: CadeusTheGreat

content/en-us/sound/objects.md

@@ -234,11 +234,7 @@ sound:Play()
 -- Start checking if emitter should be enabled
 RunService.Heartbeat:Connect(function()
 	-- Enable the emitter within a time range of the audio; otherwise disable it
-	if sound.TimePosition >= 5 and sound.TimePosition < 20 then
-		emitter.Enabled = true
-	else
-		emitter.Enabled = false
-	end
+	emitter.Enabled = sound.TimePosition >= 5 and sound.TimePosition < 20
 end)
 ```
 

content/en-us/tutorials/fundamentals/coding-5/intro-to-arrays.md

@@ -202,11 +202,7 @@ Use the array size to check when it's time to cycle back to the first piece of d
       local dialogue = dialogueArray[dialogueIndex]
       Chat:Chat(head, dialogue)
 
-      if dialogueIndex == #dialogueArray then
-        dialogueIndex = 1
-      else
-        dialogueIndex += 1
-      end
+      dialogueIndex = if dialogueIndex == #dialogueArray then 1 else dialogueIndex + 1
     end
    ```
 
@@ -239,12 +235,7 @@ This script used an array to create a list of possible dialogue lines for a Non-
       local dialogue = dialogueArray[dialogueIndex]
       Chat:Chat(head, dialogue)
 
-      if dialogueIndex == #dialogueArray then
-         dialogueIndex = 1
-
-      else
-         dialogueIndex += 1
-      end
+      dialogueIndex = if dialogueIndex == #dialogueArray then 1 else dialogueIndex + 1
    end
 
    prompt.Triggered:Connect(speak)