fix: update dependency io.grpc:grpc-bom to v1.76.0 (#561)

* fix: update dependency io.grpc:grpc-bom to v1.76.0

* deps: bump Spanner bom

---------

Co-authored-by: Knut Olav Løite <koloite@gmail.com>

Author: renovate-bot

spannerlib/wrappers/spannerlib-java/pom.xml

@@ -37,7 +37,7 @@
       <dependency>
         <groupId>io.grpc</groupId>
         <artifactId>grpc-bom</artifactId>
-        <version>1.75.0</version>
+        <version>1.76.0</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>