feat(intergations): add support for lessonly api

[hassan254-prog]

Describe your changes

• Added configuration for lessonly in providers.yaml
• Added lessonly to docs-v2.
• Added lessonly pages for Supported API groups in mint.json.
• Added lessonly SVG file in template-logos folder.
• Consolidate lessonly docs pages

Issue ticket number and link

EXT-57

Test

The documentation update was reviewed using npm run docs and verifying on localhost.