Reformat pull request template

[yaswant]

PR Summary

Sci/Tech Reviewer: NA
Code Reviewer: @james-bruten-mo

The PR body was adding literal line breaks as specified in the template, which was not ideal. I have removed the 80-character markdown formatting restriction from the template to improve how it displays on GitHub PRs.

As in MetOffice/lfric_core#211

Code Quality Checklist

(Some checks are automatically carried out via the CI pipeline)

• I have performed a self-review of my own code
• My code follows the project's style guidelines [style guidelines] (https://metoffice.github.io/lfric_core/how_to_contribute/index.html#how-to-contribute-index)
• Comments have been included that aid undertanding and enhance the readability of the code
• My changes generate no new warnings

Testing

NA

• I have tested this change locally, using the LFRic Apps rose-stem suite
• If any tests fail (rose-stem or CI) the reason is understood and acceptable (e.g. kgo changes)
• I have added tests to cover new functionality as appropriate (e.g. system tests, unit tests, etc.)
• Any new tests have been assigned an appropriate amount of compute resource and have tests been allocated to an appropriate testing group (i.e. the developer tests are for jobs which use a small amount of compute resource and complete in a matter of minutes)

Security Considerations

• I have reviewed my changes for potential security issues
• Sensitive data is properly handled (if applicable)
• Authentication and authorisation are properly implemented (if applicable)

Performance Impact

NA

• Performance of the code has been considered and, if applicable, suitable performance measurements have been conducted

AI Assistance and Attribution

NA

• Some of the content of this change has been produced with the assistance of Generative AI tool name (e.g., Met Office Github Copilot Enterprise, Github Copilot Personal, ChatGPT GPT-4, etc) and I have followed the Simulation Systems AI policy (including attribution labels)

Code Review

• All dependencies have been resolved
• Related Issues have been properly linked and addressed
• CLA compliance has been confirmed
• Code quality standards have been met
• Tests are adequate and have passed
• Documentation is complete and accurate
• Security considerations have been addressed
• Performance impact is acceptable

[james-bruten-mo]

Looks good to me