Reduce precision for test_case_2 in gmf_ebrisk_test to 4 decimals
Reduce precision for test_case_2 in gmf_ebrisk_test to 4 decimals

Test case is currently failing because of a mismatch at the 7th decimal place.
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine