Update BUG.md (#48539)

Let's try simplifying the template to see if people are able to give us the information we actually need.

Things like target platform should be in the logs so if they give us that we don't need to ask for it specifically. People seem to generally be good about saying "iOS only" etc. They don't seem to be good about giving us repro test cases.

.github/ISSUE_TEMPLATE/BUG.md

@@ -23,32 +23,18 @@ assignees: ''
 
 ## Steps to Reproduce
 
-<!--
-     Please tell us exactly how to reproduce the problem you are running into.
-
-     Please attach a small application (ideally just one main.dart file) that
-     reproduces the problem. You could use https://gist.github.com/ for this.
-
-     If the problem is with your application's rendering, then please attach
-     a screenshot and explain what the problem is.
--->
+<!-- You must include full steps to reproduce so that we can reproduce the problem. -->
 
-1. ...
-2. ...
-3. ...
+1. Run `flutter create bug`.
+2. Update the files as follows: ... <!-- include every file that is different from the template app! -->
+3. ... <!-- describe how to reproduce the problem -->
 
-<!--
-     Please tell us which target platform(s) the problem occurs (Android / iOS / Web / macOS / Linux / Windows)
-     Which target OS version, for Web, browser, is the test system running?
-     Does the problem occur on emulator/simulator as well as on physical devices?
--->
+**Expected results:** <!-- what did you want to see? -->
 
-**Target Platform:**
-**Target OS version/browser:**
-**Devices:**
+**Actual results:** <!-- what did you see? -->
 
-
-## Logs
+<details>
+  <summary>Logs</summary>
 
 <!--
       Run your application with `flutter run --verbose` and attach all the
@@ -72,3 +58,5 @@ assignees: ''
 
 ```
 ```
+
+</details>