chore(deps): bump langchain from 0.0.196 to 0.0.209

Bumps [langchain](https://github.com/langchain-ai/langchainjs) from 0.0.196 to 0.0.209.
- [Release notes](https://github.com/langchain-ai/langchainjs/releases)
- [Commits](langchain-ai/langchainjs@0.0.196...0.0.209)

---
updated-dependencies:
- dependency-name: langchain
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

package.json

@@ -90,7 +90,7 @@
     "jsdom": "23.0.0",
     "jsonfeed-to-rss": "3.0.7",
     "katex": "0.16.9",
-    "langchain": "0.0.196",
+    "langchain": "0.0.209",
     "lottie-react": "2.4.0",
     "mdast-util-to-hast": "13.0.2",
     "mdast-util-toc": "7.0.0",