Changed group_members to be compatiable with newest Jira LTS

[marcin-wozniak-wttech]

Hello!
We have tested that module in python with the newest JIRA LTS version 10.3.
In version 10.3 Atlassian has been decommissioned a endpoint[1] /rest/api/2/group with GET method.
They introduced a new endpoint /rest/api/2/group/member with GET method.

So I implemented it and tested on two version at 9.12 and 10.3 and it has got backword compatibility and the outputs are the same.

If I may help you please give me a shout!

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Have a great day!
Marcin

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[1] - https://confluence.atlassian.com/jirasoftware/jira-software-10-0-x-upgrade-notes-1431241649.html

[marcin-wozniak-wttech]

Hello!
After quite a few attempts, I’ve finally pushed a new version! Apologies for all the noise in that PR - I hope you're not too annoyed with me 😄

Additionally, I’ve run:

pre-commit run --all-files -v

Would you prefer me to push the reformatted code as well, or just stick to the actual changes?

Thanks!

[adehad]

Could I ask you to rebase and resolve any conflicts, hard to see your specific changes as they seem to have been squashed with other commits on the history.

[studioj]

Hello! After quite a few attempts, I’ve finally pushed a new version! Apologies for all the noise in that PR - I hope you're not too annoyed with me 😄

Additionally, I’ve run:

pre-commit run --all-files -v

Would you prefer me to push the reformatted code as well, or just stick to the actual changes?

Thanks!

keep to the actual changes please ... it will probably be clearer after that rebase which @adehad requested