Add the JupyterLab version update to the release docs

Author: krassowski

docs/Releasing.ipynb

@@ -25,25 +25,32 @@
     "- TODO: create a `release.py` script\n",
     "  [#88](https://github.com/krassowski/jupyterlab-lsp/issues/88)\n",
     "\n",
-    "The PyPI version must be updated in the following places:\n",
+    "The PyPI version (jupyter-lsp) must be updated in the following places:\n",
     "\n",
     "- `py_src/jupyter_lsp/_version.py` (canonical)\n",
     "- `azure-pipelines.yml`\n",
     "- `CHANGELOG.md`\n",
+    "- `docs/Installation.ipynb`\n",
     "\n",
     "The npm version of `jupyterlab-lsp` must be updated in the following places:\n",
     "\n",
     "- `packages/jupyterlab-lsp/package.json` (canonical)\n",
     "- `azure-pipelines.yml`\n",
     "- `packages/metapackage/package.json`\n",
     "- `CHANGELOG.md`\n",
+    "- `docs/Installation.ipynb`\n",
     "\n",
     "The npm version of `lsp-ws-connection` must be updated in the following places:\n",
     "\n",
     "- `packages/lsp-ws-connection/package.json` (canonical)\n",
     "- `packages/jupyterlab-lsp/package.json`\n",
     "- `CHANGELOG.md`\n",
     "\n",
+    "The JupyterLab version (if a newer is supported or required) needs to be updated in:\n",
+    "\n",
+    "- `README.md` (canonical)\n",
+    "- `docs/Installation.ipynb`\n",
+    "\n",
     "### Releasing:\n",
     "\n",
     "```bash\n",