docs: [texttospeech] update documentation to require certain fields (#…

…9417)

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PiperOrigin-RevId: 530345646

Source-Link: https://togithub.com/googleapis/googleapis/commit/ae157a1f8e72043fb2c801a06fc89bab711896fe

Source-Link: https://togithub.com/googleapis/googleapis-gen/commit/1798b3d0bd16c6ffc6a1cca31f316294234727bb
Copy-Tag: eyJwIjoiamF2YS10ZXh0dG9zcGVlY2gvLk93bEJvdC55YW1sIiwiaCI6IjE3OThiM2QwYmQxNmM2ZmZjNmExY2NhMzFmMzE2Mjk0MjM0NzI3YmIifQ==

java-texttospeech/README.md

@@ -20,7 +20,7 @@ If you are using Maven with [BOM][libraries-bom], add this to your pom.xml file:
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>libraries-bom</artifactId>
-      <version>26.11.0</version>
+      <version>26.14.0</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>
@@ -195,7 +195,7 @@ Java is a registered trademark of Oracle and/or its affiliates.
 [kokoro-badge-link-5]: http://storage.googleapis.com/cloud-devrel-public/java/badges/google-cloud-java/java11.html
 [stability-image]: https://img.shields.io/badge/stability-stable-green
 [maven-version-image]: https://img.shields.io/maven-central/v/com.google.cloud/google-cloud-texttospeech.svg
-[maven-version-link]: https://central.sonatype.com/artifact/com.google.cloud/google-cloud-texttospeech/2.15.0
+[maven-version-link]: https://central.sonatype.com/artifact/com.google.cloud/google-cloud-texttospeech/2.17.0
 [authentication]: https://github.com/googleapis/google-cloud-java#authentication
 [auth-scopes]: https://developers.google.com/identity/protocols/oauth2/scopes
 [predefined-iam-roles]: https://cloud.google.com/iam/docs/understanding-roles#predefined_roles