fix(docs): fix typos in PR template (#34844)

- Fix 'inthe' -> 'in the' on line 20
- Fix grammar error 'unless or add' -> 'or add' on line 30

(Replace this entire block of text)

Read the full contributing guidelines:
https://docs.langchain.com/oss/python/contributing/overview

Thank you for contributing to LangChain! Follow these steps to have your
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1. PR title: Should follow the format: TYPE(SCOPE): DESCRIPTION

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    - fix(anthropic): resolve flag parsing error
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https://github.com/langchain-ai/langchain/blob/master/.github/workflows/pr_lint.yml#L15-L33

2. PR description:

  - Write 1-2 sentences summarizing the change.
- If this PR addresses a specific issue, please include "Fixes
#ISSUE_NUMBER" in the description to automatically close the issue when
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"Depends on #PR_NUMBER" inthe description.

3. Run `make format`, `make lint` and `make test` from the root of the
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