Remove ref to non-existent Code of Conduct from PR template

[millsoper]

Why

PR template prompts PR submitters to read a file, CODE_OF_CONDUCT.md which is not present in the repo. This removes the reference from the PR template.
Ticket

What

Copy change in the PR template.

Before:

<!--
Thanks for your interest in the project. Bugs filed and PRs submitted are appreciated!

Please make sure that you are familiar with and follow the Code of Conduct for this project (found in the CODE_OF_CONDUCT.md file).

Also, please make sure you're familiar with and follow the instructions in the contributing guidelines (found in the CONTRIBUTING.md file).

Please fill out the information below to expedite the review and (hopefully) merge of your pull request!
-->

After:

<!--
Thanks for your interest in the project. Bugs filed and PRs submitted are appreciated!

Please make sure you're familiar with and follow the instructions in the contributing guidelines (found in the CONTRIBUTING.md file).

Please fill out the information below to expedite the review and (hopefully) merge of your pull request!
-->

Checklist

• Documentation updated (n/a)
• Demo added (n/a)
• Ready to be merged

[vercel]

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[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

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Latest deployment of this branch, based on commit 13cc995:

Sandbox	Source
spring-card	Configuration
spring-goo-blobs	Configuration
pmndrs/react-spring	Configuration
spring-slide	Configuration
spring-draggable-list	Configuration
spring-cards-stack	Configuration
spring-viewpager	Configuration
pmndrs/react-spring	Configuration
spring-image-fade	Configuration
spring-list-reordering	Configuration
spring-masonry	Configuration
spring-animating-auto	Configuration
spring-multistage-transition	Configuration
spring-chain	Configuration
spring-svg-filter	Configuration
pmndrs/react-spring	Configuration
spring-tree	Configuration
spring-notification-hub	Configuration
initial-rocket	Configuration
spring-notification-hub	Configuration
spring-notification-hub	Configuration