Update issue templates (#5846)

* Update issue templates

* add .net version to report a bug

* add request for code and sample projects in file a bug

* remove extra "additional context" section in suggest a feature

Author: Bri Achtman

.github/ISSUE_TEMPLATE/report-a-bug.md

@@ -0,0 +1,32 @@
+---
+name: Report a bug
+about: File a bug to help us improve ML.NET
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**System Information (please complete the following information):**
+ - OS & Version: [e.g. Windows 10] 
+ - ML.NET Version: [e.g. ML.NET v1.5.5]
+ - .NET Version: [e.g. .NET 5.0]
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior:
+1. Go to '...'
+2. Click on '....'
+3. Scroll down to '....'
+4. See error
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Screenshots, Code, Sample Projects**
+If applicable, add screenshots, code snippets, or sample projects to help explain your problem.
+
+**Additional context**
+Add any other context about the problem here.

.github/ISSUE_TEMPLATE/suggest-a-feature.md

@@ -0,0 +1,20 @@
+---
+name: Suggest a feature
+about: Suggest a feature or idea for ML.NET
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+**Additional context**
+Add any other context or screenshots about the feature request here.