github-actions: Add cargo-deny

Adds cargo-deny to scan for vulnerabilities and license issues regarding
rust crates.

GitHub Actions does not have an obvious way to loop over each of the
Cargo.toml files. To avoid hardcoding it, I worked around the problem
using a composite action that first generates the cargo-deny action by
finding all Cargo.toml files before calling this new generated action in
the master workflow.

Uses recommended deny.toml from cargo-deny repo with the following
modifications:

 ignore = ["RUSTSEC-2020-0071"]
  because chrono is dependent on the version of time with the
  vulnerability and there is no simple workaround

 multiple-versions = "allow"
  Because of the above error and other packages, there are instances
  where some crates require different versions of a crate.

 unknown-git = "allow"
  I don't see a particular issue with allowing crates from other repos.
  An alternative would be the manually set each repo we want in an
  allow-git list, but I see this as more of a nuisance that its worth.
  We could leave this as a warning (default), but to avoid clutter I'm
  going to allow it.

If deny.toml needs to be edited in the future, here's the guide:
https://embarkstudios.github.io/cargo-deny/index.html

Fixes #3359

Signed-off-by: Derek Lee <derlee@redhat.com>

ci/lib.sh

@@ -54,3 +54,13 @@ run_docs_url_alive_check()
 	git fetch -a
 	bash "$tests_repo_dir/.ci/static-checks.sh" --docs --all "github.com/kata-containers/kata-containers"
 }
+
+run_get_pr_changed_file_details()
+{
+	clone_tests_repo
+	# Make sure we have the targeting branch
+	git remote set-branches --add origin "${branch}"
+	git fetch -a
+	source "$tests_repo_dir/.ci/lib.sh"
+	get_pr_changed_file_details
+}