docs: add FOSSA License Badge for CLOMonitor

[agilgur5]

Fixes #9769

• Improve OpenSSF Scorecard checks #12031 is a follow-up specific to the security scores

Proper version of #12023 that FOSSA made automatically on integration

Motivation

• this is the last non-security check we need for CNCF CLOMonitor

  • after this, all the non-security checks will be at 100%

• note that while we already use Snyk, it actually does not support Go dep badges: https://support.snyk.io/hc/en-us/articles/360003997277-Badge-Support-for-Repositories (see also Add multiple license scanning tools check (instead of just FOSSA) cncf/clomonitor#50 (comment))

  • so use FOSSA, which Argo CD already uses and is already integrated into Argoproj

• we do also have some license checks to resolve there, I am working on those as well

  • EDIT: see chore(deps): use official versions of bufpipe and expr #12033 .
  • I also configured FOSSA to ignore bufpipe since it is licensed, but was just missing a license in older releases.
    • and also configured FOSSA to ignore a GPL devDep node-forge
      • webpack-dev-server's dep selfsigned uses it
        • it's a devDep, so not included in prod builds, and it's only used by webpack-dev-server, which is a separate process. so valid use of GPL that does not need a separate notice

Modifications

• add FOSSA badge to the README

• also rename "CII Best Practices" to its new name, "OpenSSF Best Practices"

Verification

Markdown preview looks ok to me

[agilgur5]

CLOMonitor non-security checks are now all at 100%!