docs(animations/grouped-animations): add React and Angular examples

[dillionmegida]

Description

Add StackBlitz live example for Grouped Animations

StackBlitz

Angular - https://stackblitz.com/edit/ionic-angular-grouped-animations
React - https://stackblitz.com/edit/ionic-react-grouped-animations

[liamdebeasi]

Thank you for the PR, and apologies for the delay! We appreciate you contributing to Ionic. Since this PR was opened we have added "playgrounds" to our docs which provide interactive demos of code, per-JS Framework code snippets, and a link to open the code snippets in StackBlitz. As a result, I have opened #3025 to create a playground for the "Groups Animations" demo.

Preview URL: https://ionic-docs-git-grouped-anim-ionic1.vercel.app/docs/utilities/animations#grouped-animations

I am going to close this in favor of the linked PR, but I will give you co-author credit when this PR merges. Let me know if you have any questions.

[dillionmegida]

Thank you so much Liam, for getting back to me. I have sincerely forgotten that I had this PR open 😂

And thanks for the co-author credit. Means a lot that my contribution is recognized. Also interesting to see that changes from 3 years ago, are still valid today, with the many moving parts in technologies nowadays.