NXCALS-1740 Enforce a well known dir naming for extracted nxcals spark jars
#Merge request template @acc-logging-team - please have a look for approval.
Currently the target directory that contains the extracted spark jars for nxcals is influenced by the source directory, that originally contains them. This means that for a source directory by the path: /path/to/source/spark/jars/nxcals-jars-dir, will create a directory with path: /path/to/target/spark/jars/nxcals-jars-dir.
This is not ideal, cause we need to have a well known naming for that specific directory, since based on that, we create a the coma-separated list of dependent jars that's included in our spark-defaults.conf template.
This MR enhances the corresponding role, in order to jar take the contents of a specified source directory and always push the collected jars to a directory dictated by the spark_nxcals_jars_dir_name ansible variable.
Closes NXCALS-1740