Update issue templates

.github/ISSUE_TEMPLATE/bug-report-or-unexpected-behaviour.md

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+---
+name: Bug report or unexpected behaviour
+about: Create a report to help us improve ClickHouse
+title: ''
+labels: bug
+assignees: ''
+
+---
+
+(you don't have to strictly follow this form)
+
+**Describe the bug or unexpected behaviour**
+A clear and concise description of what works not as it is supposed to.
+
+**How to reproduce**
+* Which ClickHouse server version to use
+* Which interface to use, if matters
+* Non-default settings, if any
+* `CREATE TABLE` statements for all tables involved
+* Sample data for all these tables, use [clickhouse-obfuscator](https://github.com/yandex/ClickHouse/blob/master/dbms/programs/obfuscator/Obfuscator.cpp#L42-L80) if necessary
+* Queries to run that lead to unexpected result
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Error message and/or stacktrace**
+If applicable, add screenshots to help explain your problem.
+
+**Additional context**
+Add any other context about the problem here.