Use a single version of monaco-editor

@languy We appear to be pulling in two different versions of monaco-editor:

➜ cosmos-explorer git:(master) npm ls monaco-editor
cosmos-explorer@1.0.0 /home/steve/cosmos-explorer
├─┬ @azure/cosmos-language-service@0.0.4
│ └── monaco-editor@0.15.6 deduped
├─┬ @nteract/monaco-editor@3.2.0
│ └── monaco-editor@0.18.1
└── monaco-editor@0.15.6

All the bundles with monaco contain both. Can you see if we can figure out how to just pull in one?