build(deps): bump langchain-core

Bumps [langchain-core](https://github.com/langchain-ai/langchain) from 0.3.72 to 0.3.81.
- [Release notes](https://github.com/langchain-ai/langchain/releases)
- [Commits](langchain-ai/langchain@langchain-core==0.3.72...langchain-core==0.3.81)

---
updated-dependencies:
- dependency-name: langchain-core
  dependency-version: 0.3.81
  dependency-type: direct:production
...

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

Author: dependabot[bot]

ai/generative-ai-service/Document Processing with GenAI/financial-analysis-chatbot/requirements.txt

@@ -7,7 +7,7 @@ oci
 oci-cli                     
 
 langchain==0.3.27           
-langchain-core==0.3.72      
+langchain-core==0.3.81      
 langchain-community
 
 # Additional dependencies