Merge branch 'rng-fix' into 'master'

BUGFIX: fix random number generation with parallelization

See merge request lscsoft/bilby!1273

(cherry picked from commit 089401e9)

dbfdc834 BUGFIX: switch to numpy random generators
5581fbb2 DEV: improve passing of seed to child processes
79b57f38 PRECOMMIT: precommit fixes
12cb3cf3 EXAMPLE: fix seed settings
89c4d721 TEST: update tests to use new rng method
612174fe TYPO: fix indentation
2c777b0e CI: remove py3.8 testing
36fc69ea TEST: allow almost equal for hardware differences