gha: cleanups

[cognifloyd]

• set FORCE_CHECK_ALL_FILES=true by default (see Remove FORCE_CHECK_ALL_FILES and always check all files #88)
• do not obscure the pip output with pip -q. Instead we can use gha output groups to jump past it.
• if a different branch of st2 or lint-configs is selected, then we need more than just one commit (fetch-depth: 1). So, if the branch is set to anything other than the default branch (master) then set fetch-depth: 0 so that all history gets included.

Tested at https://github.com/StackStorm-Exchange/stackstorm-test/runs/4644706724