Use packaged version of katex node module

debian/control

@@ -390,6 +390,7 @@ Depends: ${shlibs:Depends}, ${misc:Depends},
  node-js-cookie,
  node-jszip,
  node-jszip-utils,
+ node-katex,
  node-lodash (>= 4.17.15~),
  node-marked (>= 0.3~),
  node-mermaid,

debian/patches/0740-use-packaged-modules.patch

@@ -130,7 +130,7 @@ Use debian packaged node modules when available
      "diff": "^3.4.0",
      "document-register-element": "1.14.3",
      "dompurify": "^2.0.11",
-@@ -85,81 +62,51 @@
+@@ -85,81 +62,50 @@
      "editorconfig": "^0.15.3",
      "emoji-regex": "^7.0.3",
      "emoji-unicode-version": "^0.2.1",
@@ -155,7 +155,7 @@ Use debian packaged node modules when available
      "js-yaml": "^3.13.1",
 -    "jszip": "^3.1.3",
 -    "jszip-utils": "^0.0.2",
-     "katex": "^0.10.0",
+-    "katex": "^0.10.0",
 -    "lodash": "^4.17.20",
 +    "loader-utils": "^2.0.0",
      "marked": "^0.3.12",