Change templates for pull requests and submitting issues. (#617)

Co-authored-by: Naoki Shibata <shibatch.sf.net@gmail.com>

Author: shibatch

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,35 +1,3 @@
-<!-- Thank you for contributing! -->
+SLEEF project plans to adopt the following CoC in the near future. In preparation for this, we ask everyone to read and understand the CoC. Also, if you have any comments or objections, please post your thoughts at the following page.
 
-# Checklist
-
-- [ ] I have read the [contributing guidelines](https://github.com/shibatch/sleef/blob/HEAD/CONTRIBUTING.md).
-- [ ] I have considered portability of my change across platforms and architectures.
-- [ ] I have self-reviewed my code.
-- [ ] I have commented my code where necessary.
-- [ ] I have updated the documentation accordingly.
-- [ ] I have added tests that prove my fix is effective or that my feature works.
-
-# What is the purpose of this pull request?
-
-<!-- Keep only the lines that apply. -->
-
-* Fix a bug
-* Improve code quality or performance
-* Add support for a new vector extension
-* Add a workflow to GitHub Actions or add/modify a job in an existing workflow
-* Documentation update
-* Other, please explain:
-
-# What changes did you make?
-
-<!-- Give an overview of the change. -->
-
-This PR consists in...
-
-# Does this PR relate to any existing issue?
-
-Relates to/Fixes # (issue)
-
-# Is there anything you would like reviewers to focus on?
-
-Please on focus on...
+https://github.com/shibatch/nofreelunch?tab=coc-ov-file