chore(deps): update dependency proto-plus to v1.27.1 (#833)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
| [proto-plus](https://redirect.github.com/googleapis/proto-plus-python)
| `==1.26.1` → `==1.27.1` |
![age](https://developer.mend.io/api/mc/badges/age/pypi/proto-plus/1.27.1?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/proto-plus/1.26.1/1.27.1?slim=true)
|

---

### Release Notes

<details>
<summary>googleapis/proto-plus-python (proto-plus)</summary>

###
[`v1.27.1`](https://redirect.github.com/googleapis/proto-plus-python/blob/HEAD/CHANGELOG.md#1271-2026-01-30)

[Compare
Source](https://redirect.github.com/googleapis/proto-plus-python/compare/v1.27.0...v1.27.1)

##### Bug Fixes

- remove float\_precision for protobuf 7
([#&#8203;559](https://redirect.github.com/googleapis/proto-plus-python/issues/559))
([390b9d571bb5e58879137d5ac7c4cea1978e0024](https://redirect.github.com/googleapis/proto-plus-python/commit/390b9d571bb5e58879137d5ac7c4cea1978e0024))

###
[`v1.27.0`](https://redirect.github.com/googleapis/proto-plus-python/blob/HEAD/CHANGELOG.md#1270-2025-12-12)

[Compare
Source](https://redirect.github.com/googleapis/proto-plus-python/compare/v1.26.1...v1.27.0)

##### Features

- Add classifier for Python 3.14
([#&#8203;544](https://redirect.github.com/googleapis/proto-plus-python/issues/544))
([d9f41512648c4551fc3e926649864c5dfe3964b2](https://redirect.github.com/googleapis/proto-plus-python/commit/d9f41512648c4551fc3e926649864c5dfe3964b2))

</details>

---

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Author: renovate-bot

requirements.txt

@@ -448,9 +448,9 @@ pip-tools==7.5.3 \
     --hash=sha256:3aac0c473240ae90db7213c033401f345b05197293ccbdd2704e52e7a783785e \
     --hash=sha256:8fa364779ebc010cbfe17cb9de404457ac733e100840423f28f6955de7742d41
     # via -r requirements.in
-proto-plus==1.26.1 \
-    --hash=sha256:13285478c2dcf2abb829db158e1047e2f1e8d63a077d94263c2b88b043c75a66 \
-    --hash=sha256:21a515a4c4c0088a773899e23c7bbade3d18f9c66c73edd4c7ee3816bc96a012
+proto-plus==1.27.1 \
+    --hash=sha256:912a7460446625b792f6448bade9e55cd4e41e6ac10e27009ef71a7f317fa147 \
+    --hash=sha256:e4643061f3a4d0de092d62aa4ad09fa4756b2cbb89d4627f3985018216f9fefc
     # via
     #   google-api-core
     #   google-cloud-spanner