deps: update google auth library dependencies to v1.40.0 (#3945)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
|
[com.google.auth:google-auth-library-credentials](https://redirect.github.com/googleapis/google-auth-library-java)
| `1.39.1` -> `1.40.0` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.auth:google-auth-library-credentials/1.40.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.auth:google-auth-library-credentials/1.39.1/1.40.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
|
[com.google.auth:google-auth-library-oauth2-http](https://redirect.github.com/googleapis/google-auth-library-java)
| `1.39.1` -> `1.40.0` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.auth:google-auth-library-oauth2-http/1.40.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.auth:google-auth-library-oauth2-http/1.39.1/1.40.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
|
[com.google.auth:google-auth-library-bom](https://redirect.github.com/googleapis/google-auth-library-java)
| `1.39.1` -> `1.40.0` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.auth:google-auth-library-bom/1.40.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.auth:google-auth-library-bom/1.39.1/1.40.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.

---

### Release Notes

<details>
<summary>googleapis/google-auth-library-java
(com.google.auth:google-auth-library-credentials)</summary>

###
[`v1.40.0`](https://redirect.github.com/googleapis/google-auth-library-java/blob/HEAD/CHANGELOG.md#1400-2025-10-14)

[Compare
Source](https://redirect.github.com/googleapis/google-auth-library-java/compare/v1.39.1...v1.40.0)

##### Features

- Add projectId getter to GoogleCredentials
([#&#8203;1813](https://redirect.github.com/googleapis/google-auth-library-java/issues/1813))
([c3d9ee0](https://redirect.github.com/googleapis/google-auth-library-java/commit/c3d9ee09df30a26586b0e834cfda7763fd7854f5))
- Support user defined or json defined scopes for impersonated token
([#&#8203;1815](https://redirect.github.com/googleapis/google-auth-library-java/issues/1815))
([84fc566](https://redirect.github.com/googleapis/google-auth-library-java/commit/84fc566d92f03e648cd82a8860fb191520bb6c7e))

##### Dependencies

- Bump guava to v33.5.0
([#&#8203;1825](https://redirect.github.com/googleapis/google-auth-library-java/issues/1825))
([79f0a35](https://redirect.github.com/googleapis/google-auth-library-java/commit/79f0a353e12a8206584e9031989861ca6abaaf85))

</details>

---

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rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about these
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---

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---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/googleapis/sdk-platform-java).

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Co-authored-by: Lawrence Qiu <lawrenceqiu@google.com>

Author: renovate-bot

gapic-generator-java-pom-parent/pom.xml

@@ -28,7 +28,7 @@
         consistent across modules in this repository -->
     <javax.annotation-api.version>1.3.2</javax.annotation-api.version>
     <grpc.version>1.71.0</grpc.version>
-    <google.auth.version>1.39.1</google.auth.version>
+    <google.auth.version>1.40.0</google.auth.version>
     <google.http-client.version>2.0.2</google.http-client.version>
     <gson.version>2.12.1</gson.version>
     <guava.version>33.5.0-jre</guava.version>

gax-java/dependencies.properties

@@ -37,8 +37,8 @@ version.io_grpc=1.71.0
 #   2) Replace all characters which are neither alphabetic nor digits with the underscore ('_') character
 maven.com_google_api_grpc_proto_google_common_protos=com.google.api.grpc:proto-google-common-protos:2.61.1
 maven.com_google_api_grpc_grpc_google_common_protos=com.google.api.grpc:grpc-google-common-protos:2.61.1
-maven.com_google_auth_google_auth_library_oauth2_http=com.google.auth:google-auth-library-oauth2-http:1.39.1
-maven.com_google_auth_google_auth_library_credentials=com.google.auth:google-auth-library-credentials:1.39.1
+maven.com_google_auth_google_auth_library_oauth2_http=com.google.auth:google-auth-library-oauth2-http:1.40.0
+maven.com_google_auth_google_auth_library_credentials=com.google.auth:google-auth-library-credentials:1.40.0
 maven.io_opentelemetry_opentelemetry_api=io.opentelemetry:opentelemetry-api:1.47.0
 maven.io_opencensus_opencensus_api=io.opencensus:opencensus-api:0.31.1
 maven.io_opencensus_opencensus_contrib_grpc_metrics=io.opencensus:opencensus-contrib-grpc-metrics:0.31.1