docs: Remove templates in readme

[Mingqi2]

docs: Remove templates in readme

Issue: 404 when you click the LangChain Templates in readme. As templates dir has been removed on latest langchain master.

Fix: Just remove it to avoid 404 as example dirs is enough, look like (my local vs code)

[cla-bot]

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[Mingqi2]

Hi @eyurtsev , I see you're the active maintainer for this repo. could you review my CLA request? I have submitted it! very appreciated!

In order for us to review and merge your code, please complete the Individual Contributor License Agreement here https://forms.gle/AQFbtkWRoHXUgipM6 .

It's best if you would like to review this PR too. Thank you!