Update RunService.yaml (#1079)

## Changes

<!-- Please summarize your changes. -->
I have changed the description of the `DeltaTimeSim` param to correctly
say it is the time since the last simulation step instead of the last
frame

<!-- Please link to any applicable information (forum posts, bug
reports, etc.). -->
```lua
local dt1 = game:GetService("RunService").PreSimulation:Wait()
local dt2 = game:GetService("RunService").PreSimulation:Wait() 
print(dt1, dt2) -- almost always outputs the same values, the physics simulation runs at a fixed 240hz afaik which would result in this
```

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- [X] To the best of my knowledge, all proposed changes are accurate.

---------

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

Author: ColRealPro

content/en-us/reference/engine/classes/RunService.yaml

@@ -567,8 +567,9 @@ events:
       Fires every frame, after the physics simulation has completed.
     description: |
       The `PostSimulation` event fires every frame, after the physics simulation
-      has completed. The `deltaTimeSim` argument indicates the time that has
-      elapsed since the previous frame.
+      has completed. The `deltaTimeSim` argument indicates the time that the
+      current frame has stepped the physics simulation, not accounting for
+      physics throttling.
 
       This event is useful for making final adjustments to the outcome of the
       simulation. Following this phase, the engine triggers the
@@ -579,7 +580,8 @@ events:
         type: double
         default:
         summary: |
-          The time (in seconds) that has elapsed since the previous frame.
+          The time (in seconds) that the current frame has stepped the physics
+          simulation, not accounting for physics throttling.
     tags: []
     deprecation_message: ''
     security: None
@@ -592,7 +594,7 @@ events:
     description: |
       The `PreAnimation` event fires every frame, prior to the physics
       simulation but after rendering. The `deltaTimeSim` argument indicates the
-      time that has elapsed since the previous frame.
+      time that the current frame has stepped animations.
 
       This event is useful for modifying animation objects, such as adjusting
       their speed or priority. Once the `PreAnimation` event is complete, the
@@ -607,7 +609,7 @@ events:
         type: double
         default:
         summary: |
-          The time (in seconds) that has elapsed since the previous frame.
+          The time (in seconds) that the current frame has stepped animations.
     tags: []
     deprecation_message: ''
     security: None
@@ -656,7 +658,8 @@ events:
       The `PreSimulation` event (replacement for
       `Class.RunService.Stepped|Stepped`) fires every frame, prior to the
       physics simulation. The `deltaTimeSim` argument indicates the time that
-      has elapsed since the previous frame.
+      the current frame will step the physics simulation, not accounting for
+      physics throttling.
 
       This event is useful for adjusting properties like velocity or forces just
       before they're applied as part of the simulation. The simulation then
@@ -669,7 +672,8 @@ events:
         type: double
         default:
         summary: |
-          The time (in seconds) that has elapsed since the previous frame.
+          The time (in seconds) that the current frame will step the physics
+          simulation, not accounting for physics throttling.
     tags: []
     deprecation_message: ''
     security: None
@@ -679,7 +683,13 @@ events:
   - name: RunService.RenderStepped
     summary: |
       Fires every frame, prior to the frame being rendered.
-    description: ''
+    description: |
+      Fires every frame, prior to the frame being rendered.
+
+      ##### Migration Note
+
+      This event has been superseded by `Class.RunService.PreRender|PreRender`
+      which should be used for new work.
     code_samples: []
     parameters:
       - name: deltaTime
@@ -688,17 +698,21 @@ events:
         summary: |
           The time (in seconds) that has elapsed since the previous frame.
     tags: []
-    deprecation_message: |
-      This event has been superseded by `Class.RunService.PreRender|PreRender`
-      which should be used for new work.
+    deprecation_message: ''
     security: None
     thread_safety: Unsafe
     capabilities: []
     writeCapabilities: []
   - name: RunService.Stepped
     summary: |
       Fires every frame, prior to the physics simulation.
-    description: ''
+    description: |
+      Fires every frame, prior to the physics simulation.
+
+      ##### Migration Note
+      
+      This event has been superseded by `Class.RunService.PreSimulation|PreSimulation`
+      which should be used for new work.
     code_samples: []
     parameters:
       - name: time
@@ -713,10 +727,7 @@ events:
         summary: |
           The time (in seconds) that has elapsed since the previous frame.
     tags: []
-    deprecation_message: |
-      This event has been superseded by
-      `Class.RunService.PreSimulation|PreSimulation` which should be used for
-      new work.
+    deprecation_message: ''
     security: None
     thread_safety: Unsafe
     capabilities: []