Remove flink streaming scala dependency as we no longer need it (#327)

## Summary

Remove flink streaming scala dependency as we no longer need it
otherwise we will run into runtime error saying flink-shaded-guava
package not found

## Checklist
- [ ] Added Unit Tests
- [x] Covered by existing CI
- [ ] Integration tested
- [ ] Documentation update



<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **Bug Fixes**
- Improved dependency handling to reduce the risk of runtime errors such
as class incompatibilities.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: kumar-zlai

tools/build_rules/flink/BUILD

@@ -6,9 +6,6 @@ java_binary(
     name = "flink",
     main_class = "None",  #hack
     runtime_deps = [
-        # mark the flink-streaming scala as provided as otherwise we end up with some extra Flink classes in our jar
-        # and errors at runtime like: java.io.InvalidClassException: org.apache.flink.streaming.api.scala.DataStream$$anon$1; local class incompatible
-        scala_artifact("org.apache.flink:flink-streaming-scala"),
         # Exclude Guava from the assembled JAR
         # Else we hit an error - java.lang.NoSuchMethodError: com.google.common.base.Preconditions.checkArgument(...)
         maven_artifact("com.google.guava:guava"),