chore(bootstrap-vue): Drop most of the build system

What does this MR do?

chore(bootstrap-vue): Use our env variable to determine VUE version

Using our env variable in jest/CI to determine whether vue@2 or vue@3 is used.

chore(bootstrap-vue): Replace jiti with native ESM script

And add a new bash script to wrap the metadata check

chore(bootstrap-vue): Remove compilation of CSS

We are in no need for a compiled CSS file because we are consuming the SCSS source. So, we can simply get rid of all related dependencies.

chore(bootstrap-vue): Remove JS build dependencies

We are consuming the bootstrap-vue code from source, so we can drop most babel, rollup and terser related dependencies.

chore(bootstrap-vue): Remove babel-eslint dependency

Apparently eslint is able to understand all of bootstrap-vue, without the babel-eslint dependency.

Screenshots or screen recordings

Integration merge requests

• GitLab: mr_url
• CustomersDot: mr_url
• Status Page: mr_url

Does this MR meet the acceptance criteria?

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• Added the ~"component:*" label(s) if applicable.

Security

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Accessibility

If this MR adds or modifies a component, take a few moments to review the following:

• All actions and functionality can be done with a keyboard.
• Links, buttons, and controls have a visible focus state.
• All content is presented in text or with a text equivalent. For example, alt text for SVG, or aria-label for icons that have meaning or perform actions.
• Changes in a component’s state are announced by a screen reader. For example, changing aria-expanded="false" to aria-expanded="true" when an accordion is expanded.
• Color combinations have sufficient contrast.