bump grpc version to 1.75.0 (#2525)

Signed-off-by: emiliyank <e.kadiyski@gmail.com>

Author: emiliyank

hiero-dependency-versions/build.gradle.kts

@@ -9,7 +9,7 @@ plugins {
 group = "org.hiero"
 
 val bouncycastle = "1.80"
-val grpc = "1.74.0"
+val grpc = "1.75.0"
 val protobuf = "4.31.1"
 val slf4j = "2.0.17"
 val mockito = "5.19.0"