Add issue template (#1275)

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,37 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: "[BUG]"
+labels: ''
+assignees: ''
+
+---
+
+The Issue tracker is **ONLY** used for reporting bugs. New features should be discussed on our [Slack channel](https://ghostfolio.slack.com) or in [Discussions](https://github.com/ghostfolio/ghostfolio/discussions).
+
+**Describe the bug**
+<!-- A clear and concise description of what the bug is. -->
+
+**To Reproduce**
+Steps to reproduce the behavior:
+1.
+2.
+3.
+4.
+
+**Expected behavior**
+<!-- A clear and concise description of what you expected to happen. -->
+
+**Screenshots**
+<!-- If applicable, add screenshots to help explain your problem. -->
+
+**Logs**
+<!-- If applicable, add logs to help explain your problem. -->
+
+**Environment (please complete the following information):**
+ - Ghostfolio Version [e.g. 1.194.0]
+ - Browser [e.g. chrome]
+ - OS
+
+**Additional context**
+<!-- Add any other context about the problem here. -->