remove secretgroup from default config

[zricethezav]

Description:

Cleans up the default gitleaks.toml by removing the unnecessary secretGroup field. Note that secretGroup still works.

Checklist:

• Does your PR pass tests?
• Have you written new tests for your changes?
• Have you lint your code locally prior to submission?

[zricethezav]

tests are failing because this change results in a capture group being actually used https://github.com/gitleaks/gitleaks/blob/master/testdata/config/simple.toml#L7 fixt

Kinda wanna go forth with this change as I would like to enforce one capture group per regex by default

[rgmz]

I was playing with a change that would support multiple secret groups. The main motivation being that you can do: password: (?:("[^"]")|('[^']')) rather than something like password: ["'](.+)["'] or password: ("[^"]"|'[^']') which is less precise.

Edit: I realized that I misread your comment. You want every pattern to have one capture group by default, not only one capture group ever.