Add github template for issues

[markov00]

Add a first basic issue template to keep track of kibana cross issues:
The template can have a checklist like the following:

<!--
GitHub is reserved for bug reports and feature requests. The best place
to ask a general question is at the Elastic Discourse forums at
https://discuss.elastic.co. If you are in fact posting a bug report or
a feature request, please include one and only one of the below blocks
in your new issue.
-->

<!--
If you are filing a bug report, please remove the below feature
request block and provide responses for all of the below items.
-->

**Elastic Chart version**:

**Browser version**:

**Browser OS version**:

**Description of the problem including expected versus actual behavior**:

**Steps to reproduce**:
 1.
 2.
 3.

**Errors in browser console (if relevant)**:

**Kibana Cross Issues**:

**Checklist**
[] every related Kibana issue is listed under `Kibana Cross Issues:` list
[] `kibana cross issue` tag is associated to the issue if any kibana cross issue is present

[markov00]

🎉 This issue has been resolved in version 1.1.1 🎉

The release is available on:

• GitHub release
• npm package (@latest dist-tag)

Your semantic-release bot 📦🚀