Direction applies to all class diagrams in a markdown file

[lonix1]

When there are multiple class diagrams in a single markdown file, the same direction is applied to all of them.

e.g.

## Title

```mermaid
classDiagram
  direction RL
  A <|-- B
```

## Title

```mermaid
%% this class diagram will also have direction RL
classDiagram
  Animal <|-- Dog
```

The workaround is to redeclare the direction for every diagram. Not nice.

I'm unsure whether this is a problem in the extension, or the underlying mermaid library?