Add two simple stories for ci_icon

What does this MR do and why?

Add two simple stories for ci_icon so we can verify its appearance more easily. Move variants and usages can be added later.

Related MRs

• Move ci_icon.vue to its own directory (!139227 - merged)
• Add two simple stories for ci_icon (!139239 - merged) ☝ you are here!
• Draft: Use default icon size in CI status icons (!139243 - closed)

Screenshots or screen recordings

http://localhost:9002/?path=/story/vue-shared-ci-icon--default	http://localhost:9002/?path=/story/vue-shared-ci-icon--with-show-status-text

How to set up and validate locally

1. $ yarn storybook:install
2. $ yarn storybook:start
3. Select ci_icon in vue_shared. Check two stories are available.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #434472 (closed)