DOC-2498: The command `MarkdownInsert` is now registered immediately and operates in an async manner, instead of waiting for resources before registering the command.

[kemister85]

Ticket: DOC-2498

Site: Staging branch

Changes:

• Improvement and Added fix for TINY-11280

Pre-checks:

• [x] Branch prefixed with feature/<version>/, hotfix/<version>/, staging/<version>/, or release/<version>/.

Review:

• [ ] Documentation Team Lead has reviewed