Bump the app group with 4 updates

Bumps the app group with 4 updates: [anthropic](https://github.com/anthropics/anthropic-sdk-python), [duckduckgo-search](https://github.com/deedy5/duckduckgo_search), [langchain](https://github.com/langchain-ai/langchain) and [langsmith](https://github.com/langchain-ai/langsmith-sdk).


Updates `anthropic` from 0.7.8 to 0.8.0
- [Release notes](https://github.com/anthropics/anthropic-sdk-python/releases)
- [Changelog](https://github.com/anthropics/anthropic-sdk-python/blob/main/CHANGELOG.md)
- [Commits](https://github.com/anthropics/anthropic-sdk-python/compare/v0.7.8...v0.8.0)

Updates `duckduckgo-search` from 4.0.0 to 4.1.0
- [Release notes](https://github.com/deedy5/duckduckgo_search/releases)
- [Commits](https://github.com/deedy5/duckduckgo_search/compare/v4.0.0...v4.1.0)

Updates `langchain` from 0.0.350 to 0.0.351
- [Release notes](https://github.com/langchain-ai/langchain/releases)
- [Commits](https://github.com/langchain-ai/langchain/compare/v0.0.350...v0.0.351)

Updates `langsmith` from 0.0.71 to 0.0.72
- [Release notes](https://github.com/langchain-ai/langsmith-sdk/releases)
- [Commits](https://github.com/langchain-ai/langsmith-sdk/compare/v0.0.71...v0.0.72)

---
updated-dependencies:
- dependency-name: anthropic
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: app
- dependency-name: duckduckgo-search
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: app
- dependency-name: langchain
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: app
- dependency-name: langsmith
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: app
...

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

requirements.txt

@@ -1,11 +1,11 @@
-anthropic==0.7.8
+anthropic==0.8.0
 beautifulsoup4==4.12.2
 black==23.12.0
 certifi>=2023.7.22 # not directly required, pinned by Snyk to avoid a vulnerability
-duckduckgo-search==4.0.0
+duckduckgo-search==4.1.0
 faiss-cpu==1.7.4
-langchain==0.0.350
-langsmith==0.0.71
+langchain==0.0.351
+langsmith==0.0.72
 mypy==1.7.1
 numexpr==2.8.8
 numpy>=1.22.2 # not directly required, pinned by Snyk to avoid a vulnerability