Update PR template

[eNeRGy164]

Description

Often, people tend to write the description of the PR under the important sections. This makes it much harder to read the important reason of the PR when using GitHub on smaller devices.

This PR adds a comment above IMPORTANT

Current situation

1. Inbox only shows one line, which now shows the IMPORTANT header
   

2. PR overview still only shows the checklist
   

3. Only after extending the content, and scrolling down, the change description becomes visible,
   

IMPORTANT

• If the PR touches the public API, the changes have been approved in a separate issue with the "api-approved" label.
• The code complies with the Coding Guidelines for C#.
• The changes are covered by unit tests which follow the Arrange-Act-Assert syntax and the naming conventions such as is used in these tests.
• If the PR adds a feature or fixes a bug, please update the release notes with a functional description that explains what the change means to consumers of this library, which are published on the website.
• If the PR changes the public API the changes needs to be included by running AcceptApiChanges.ps1 or AcceptApiChanges.sh.
• If the PR affects the documentation, please include your changes in this pull request so the documentation will appear on the website.
  • Please also run ./build.sh --target spellcheck or .\build.ps1 --target spellcheck before pushing and check the good outcome

[coveralls]

Pull Request Test Coverage Report for Build 4757711288

Warning: This coverage report may be inaccurate.

We've detected an issue with your CI configuration that might affect the accuracy of this pull request's coverage report.
To ensure accuracy in future PRs, please see these guidelines.
A quick fix for this PR: rebase it; your next report should be accurate.

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 97.186%

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Totals
Change from base Build 4756846326:	0.0%
Covered Lines:	12844
Relevant Lines:	13087

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💛 - Coveralls

[dennisdoomen]

Thank you. It always annoys me that people put the description below the "important" section.

[jnyrup]

It always annoys me that people put the description below the "important" section.