[Java] [Integration Tests] Move all the gcs input files as part of codebase

[shashank-google]

Eg:
gcs.spanner.input.location=gs://dataproc-templates/data/avro/empavro
gcs.gcs.input.location=gs://dataproc-templates/integration-testing/gcstogcs/csvtoavro/csv/cities.csv
gcs.bigtable.input.location=gs://dataproc-templates/data/csv/GCSToBigTable_cities.csv
gcs.bigquery.input.location=gs://dataproc-templates/integration-testing/gcstobigquery/cities.csv
text.bigquery.input.location=gs://dataproc-templates/data/deflate

should be checked in java/.ci/

Then in stage('Reset Resources') of JenkinsFile it should be overwritten before running the tests.