Issue 5793: Add root cause to bug report template. (#5794)
Issue 5793: Add root cause to bug report template. (#5794)

Adds a comment about describing the root cause in the bug report issue template.

Signed-off-by: Flavio Junqueira (fpj) <3143f522c4835f95078812226e7dab45695d0369@apache.org>
pravega/pravega,pravega/pravega,pravega/pravega