Add timeout to ICU4J exhaustive test CI failure step. Update Git LFS steps for ICU4J.
The ICU4J exhaustive tests don't have a timeout on the "Check for failures part", so if the command fails then the build will hang for the remainder of the total timeout (1 hour 40 minutes).
This blocks an entire build line until it times out.
Additionally, the syntax for the Git LFS check out for Azure Pipelines has change slightly, which means that the Exhaustive tests for ICU4J have been failing. We’ll need to update the YAML files for this as well.