No diagram found in mardown file when using whitespace in definition.

[nklsla]

Describe the bug
When trying to generate images from a markdown (.md) file the CLI does not recognize the mermaid definiton.

To Reproduce
Steps to reproduce the behavior:

Install and run the docker alternative using
docker run --rm -u `id -u`:`id -g` -v /path/to/diagrams:/data minlag/mermaid-cli -i diagram.mmd

Define the mermaid diagram in the markdown file with a whitespace like so:

::: mermaid
graph TD
..
:::

Expected behavior
To get an generated image

Desktop (please complete the following information):

• OS: Windows 11, running Ubuntu 22.04 on WSL 2.

Additional context
Either this could be fixed or made clear in documentation/help command from the CLI.

If only documentation is needed I could do a PR myself.