Fix: typo in environment-declarations.md

[Gohan61]

Removed 'the' from the sentence as it is followed by 'your', so the sentence was incorrect.

---

• I’ve reviewed the contributor guide and applied the relevant portions to this PR.
• This PR doesn't contain automatically generated corrections or text (Grammarly, LLMs, and similar).
• This PR follows the Google Developer Documentation Style Guidelines — for example, it doesn't use i.e. or e.g., and it avoids I and we (first person).
• This PR uses semantic line breaks of 80 characters or fewer.

Contribution guidelines:

• See our contributor guide for general expectations for PRs.
• Larger or significant changes should be discussed in an issue before creating a PR.
• Code changes should generally follow the Dart style guide and use dart format.
• Updates to code excerpts indicated by <?code-excerpt need to be updated in their source .dart file as well.

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[parlough]

/gcbrun

[parlough]

Nice catch! Thanks for fixing this :)

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