New feature :- Add _animations.css with new animations

[rajputpritesh1]

Created a new file named _animations.css in the Bootstrap repository. This file contains several useful animations that can be utilized across various components and elements within Bootstrap. These animations are designed to enhance user experience and add visual appeal to web projects. The animations have been carefully crafted to ensure compatibility and seamless integration with Bootstrap's existing styles and functionality. This contribution aims to expand the animation options available to Bootstrap users, providing them with more creative possibilities for designing modern and engaging interfaces.

Description

Motivation & Context

Type of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (non-breaking change)
• Breaking change (fix or feature that would change existing functionality)

Checklist

• I have read the contributing guidelines
• My code follows the code style of the project (using npm run lint)
• My change introduces changes to the documentation
• I have updated the documentation accordingly
• I have added tests to cover my changes
• All new and existing tests passed

Live previews

• https://deploy-preview-{your_pr_number}--twbs-bootstrap.netlify.app/

Related issues

[julien-deramond]

Thanks for this PR @rajputpritesh1

Having some animations could be interesting, but this is probably something to discuss collectively in terms of types of animations, durations (+ customization of durations), relationship with $enable-transitions, etc.

Moreover, this new feature should be documented.

There's also a lint error in this new file, that is maybe rather a helper, IDK.

[AgentSmith0]

Here is an interesting implementation I've found: https://mdbootstrap.com/docs/standard/content-styles/animations/