Update bug_report.md

Implementing Tim's suggestions

.github/ISSUE_TEMPLATE/bug_report.md

@@ -2,26 +2,30 @@
 name: Bug report
 about: Report bugs or errors
 title: ''
-labels: ''
+labels: ['bug']
 assignees: ''
 
 ---
 
 **Describe the bug**
+
 A clear and concise description of what the bug is.
 
 **To Reproduce**
+
 Steps to reproduce the behavior:
 1. Run code '...'
-2. Expect this error '....'
+2. Expect this error '...'
 
 **Expected behavior**
+
 A clear and concise description of what you expected to happen.
 
 **Environment, if relevant:**
- - OS: [e.g. iOS]
+
+ - OS: [e.g. Ubuntu 22.04, macOS 14.5, etc.]
  - R Version [e.g. 4.4.0] (can obtain with command `R --version`)
  - Python Version [e.g. 3.10] (can obtain with command `python --version`)
- - flepiMoP branch commit, if relevant 
+ - flepiMoP branch and/or commit if relevant (`git rev-parse HEAD`)