25-2 Docs: Remove version 25.1 remark about vector index

[azevaykin]

Changelog entry

In version 25.2, the enable_vector_index feature flag is enabled by default, so these remarks are irrelevant.

Changelog category

• Documentation (changelog entry is not required)

Description for reviewers

...

[github-actions]

⚪ 2025-09-23 14:33:50 UTC Pre-commit check linux-x86_64-relwithdebinfo for 945daa6 has started.
⚪ 2025-09-23 14:34:06 UTC Artifacts will be uploaded here
⚪ 2025-09-23 14:36:25 UTC ya make is running...
🟢 2025-09-23 14:36:31 UTC Tests successful.

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
0	0	0	0	0	0

🟢 2025-09-23 14:36:38 UTC Build successful.

[github-actions]

✅ Documentation build

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Build logs

Warnings (4)

⚠️ ru/changelog-server.md: 12: MD009 / no-trailing-spaces Trailing spaces [Expected: 0 or 2; Actual: 1]

⚠️ ru/recipes/transfer/nginx.md: 146: MD034 / no-bare-urls Bare URL used [Context: "http://localhost/"]

⚠️ ru/yql/reference/syntax/alter-transfer.md: 14: MD051 / link-fragments Link fragments should be valid [Context: "lambda-функция"]

⚠️ ru/yql/reference/syntax/create-transfer.md: 16: MD051 / link-fragments Link fragments should be valid [Context: "lambda-функция"]

[github-actions]

⚪ 2025-09-23 14:37:48 UTC Pre-commit check linux-x86_64-release-asan for 945daa6 has started.
⚪ 2025-09-23 14:37:52 UTC Artifacts will be uploaded here
⚪ 2025-09-23 14:40:20 UTC ya make is running...
🟢 2025-09-23 14:40:26 UTC Tests successful.

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
0	0	0	0	0	0

🟢 2025-09-23 14:40:32 UTC Build successful.

[github-actions]

🟢 2025-09-23 14:39:10 UTC The validation of the Pull Request description is successful.