Use mermaid fork with d3v5 support

debian/patches/0760-use-mermaid-fork.patch

@@ -0,0 +1,11 @@
+--- a/package.json
++++ b/package.json
+@@ -98,7 +98,7 @@
+     "jszip-utils": "^0.0.2",
+     "katex": "^0.10.0",
+     "marked": "^0.3.12",
+-    "mermaid": "^8.2.6",
++    "mermaid": "pravi/mermaid#switch-to-dagre-d3-with-dist",
+     "monaco-editor": "^0.15.6",
+     "monaco-editor-webpack-plugin": "^1.7.0",
+     "mousetrap": "^1.4.6",

debian/patches/series

@@ -25,3 +25,4 @@
 0730-install-graphql-tag.patch
 0740-use-packaged-modules.patch
 0750-fix-relative-paths.patch
+0760-use-mermaid-fork.patch