Remove few dependencies which are not required for ERD Tool.

web/package.json

@@ -79,7 +79,6 @@
     "bootstrap4-toggle": "3.4.0",
     "bowser": "2.1.2",
     "browserify": "~16.2.3",
-    "canvg": "^3.0.7",
     "chart.js": "^2.9.3",
     "closest": "^0.0.1",
     "codemirror": "^5.54.0",
@@ -88,8 +87,6 @@
     "dagre": "^0.8.4",
     "dropzone": "^5.5.1",
     "exports-loader": "~0.7.0",
-    "html-to-image": "^0.1.1",
-    "html2canvas": "^1.0.0-rc.7",
     "immutability-helper": "^3.0.0",
     "imports-loader": "^0.8.0",
     "ip-address": "^5.8.9",