fix: upgrade io.grpc:grpc-core from 1.64.0 to 1.68.0

Snyk has created this PR to upgrade io.grpc:grpc-core from 1.64.0 to 1.68.0.

See this package in maven:
io.grpc:grpc-core

See this project in Snyk:
https://app.snyk.io/org/b.w.donnelly1/project/b4c1d3ed-8a7c-44e0-8c08-198fb8227ffc?utm_source=github&utm_medium=referral&page=upgrade-pr

pom.xml

@@ -71,7 +71,7 @@
 
 
     <properties>
-        <grpc.version>1.64.0</grpc.version>
+        <grpc.version>1.68.0</grpc.version>
 
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>