## Summary

Update Vega dependencies to 6.x.

This pull request updates the project's Vega and Vega-Lite dependencies
to their latest major versions.

**Dependency Upgrades and Import Handling**

- Upgraded `vega`, `vega-lite`, `vega-interpreter`, `vega-tooltip`, and
related libraries to their latest major versions in `package.json`, and
updated their import paths throughout the codebase.

- Removed legacy Webpack and Storybook configuration for the old `vega`
build, including `noParse` rules and aliases, and updated the import
resolver to point to the new `vega-lite` and `vega-tooltip` build
directories.

**Testing and TypeScript Support**

- Added a Jest setup mock for `vega` and `vega-lite` to ensure tests run
correctly with the new versions, and updated Jest transform ignore
patterns to support new Vega-related packages.
- Updated `tsconfig.base.json` to include type definitions for
`vega-lite` and `vega-tooltip`.

**Babel and Build Tools**

- Added `@babel/plugin-syntax-import-attributes` to dependencies and
Babel preset to enable the new import attributes syntax.

**Test Snapshots**

- Updated Vega visualization test snapshots to reflect the new
rendering/output from upgraded dependencies.

---------

Co-authored-by: Tiago Costa <tiago.costa@elastic.co>
(cherry picked from commit d8c23ae)

# Conflicts:
#	package.json
#	src/platform/packages/shared/kbn-test/jest-preset.js