chore(deps): update dependency com.google.cloud:libraries-bom to v26.21.0 (#1408)

* chore(deps): update dependency com.google.cloud:libraries-bom to v26.21.0

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

---------

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: renovate-bot

README.md

@@ -19,7 +19,7 @@ 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>26.20.0</version>
+      <version>26.21.0</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>

samples/native-image-sample/pom.xml

@@ -29,7 +29,7 @@
       <dependency>
         <groupId>com.google.cloud</groupId>
         <artifactId>libraries-bom</artifactId>
-        <version>26.20.0</version>
+        <version>26.21.0</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>

samples/snippets/pom.xml

@@ -29,7 +29,7 @@
       <dependency>
         <groupId>com.google.cloud</groupId>
         <artifactId>libraries-bom</artifactId>
-        <version>26.20.0</version>
+        <version>26.21.0</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>