Set mermaid output type

docs/conf.py

@@ -49,6 +49,7 @@
 # optional to use directive options
 myst_enable_extensions = ["attrs_block"]
 mermaid_params = ['-p' 'puppeteer-config.json']
+mermaid_output_format = "png"
 
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']