chore(deps): update dependency com.google.cloud:libraries-bom to v26.1.5 (#2170)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.cloud:libraries-bom](https://cloud.google.com/java/docs/bom) ([source](https://togithub.com/googleapis/java-cloud-bom)) | `26.1.4` -> `26.1.5` | [![age](https://badges.renovateapi.com/packages/maven/com.google.cloud:libraries-bom/26.1.5/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.cloud:libraries-bom/26.1.5/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.cloud:libraries-bom/26.1.5/compatibility-slim/26.1.4)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.cloud:libraries-bom/26.1.5/confidence-slim/26.1.4)](https://docs.renovatebot.com/merge-confidence/) |

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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>26.1.4</version>
+      <version>26.1.5</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>
@@ -49,7 +49,7 @@ If you are using Maven without BOM, add this to your dependencies:
 If you are using Gradle 5.x or later, add this to your dependencies:
 
 ```Groovy
-implementation platform('com.google.cloud:libraries-bom:26.1.4')
+implementation platform('com.google.cloud:libraries-bom:26.1.5')
 
 implementation 'com.google.cloud:google-cloud-spanner'
 ```

samples/native-image/pom.xml

@@ -28,7 +28,7 @@
       <dependency>
         <groupId>com.google.cloud</groupId>
         <artifactId>libraries-bom</artifactId>
-        <version>26.1.4</version>
+        <version>26.1.5</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>

samples/snippets/pom.xml

@@ -33,7 +33,7 @@
       <dependency>
         <groupId>com.google.cloud</groupId>
         <artifactId>libraries-bom</artifactId>
-        <version>26.1.4</version>
+        <version>26.1.5</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>