Bump langchain-core from 0.3.66 to 0.3.80 in /Chapter12

Bumps [langchain-core](https://github.com/langchain-ai/langchain) from 0.3.66 to 0.3.80.
- [Release notes](https://github.com/langchain-ai/langchain/releases)
- [Commits](langchain-ai/langchain@langchain-core==0.3.66...langchain-core==0.3.80)

---
updated-dependencies:
- dependency-name: langchain-core
  dependency-version: 0.3.80
  dependency-type: indirect
...

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

Author: dependabot[bot]